Please note that obs_start_time is in UT, not local time.
Clicking on the Sequence Number link will take you to the title and abstract of the proposal.
Clicking on the ObsID link will take you to the results of our search in ADS for articles we were able to link to the ObsID. Our database extends to publications that appeared three months or more ago and does not include meeting abstracts.
A 'D' in the prop_time column means a proprietary time of 1-3 months, with the default being 3 months. A '3' means a proprietary time of three months. An 'N' means the data is public.
Click here for table only
Approved/Rejected DDT Stats from Sep 1, 2021 to Present (Sep 12, 2022)
DDTs from Sep 1, 2021 to Present (Sep 12, 2022) (Part 1)
DDTs from Sep 1, 2021 to Present (Sep 12, 2022) (Part 2)
Cycle | Approved Time | Requested Time |
---|---|---|
01 | 160 | 1068 |
02 | 906.5 | 1441 |
03 | 859.477 | 1982 |
04 | 468.78 | 989.5 |
05 | 725 | 1333 |
06 | 373 | 1090.8 |
07 | 196.6 | 645.4 |
08 | 1218.2 | 1916 |
09 | 707.2 | 741 |
10 | 106 | 2333 |
11 | 218 | 623 |
12 | 497 | 1019 |
13 | 392 | 803 |
14 | 427 | 723.1 |
15 | 440 | 11375 |
16 | 662.8 | 1119.8 |
17 | 837 | 1389 |
18 | 862.8 | 1996.8 |
19 | 646.5 | 1452.5 |
20 | 785.2 | 1645 |
21 | 1000 | 1481 |
22 | 767 | 1509 |
23 | 270 | 1248 |
Target Name | Category | PI | RequestedTime | Approved Time | Instrument | Grating | Proprietary Time | Submission Date |
---|---|---|---|---|---|---|---|---|
SGBS J1740381-273712 | BH AND NS BINARIES | Maccarone | 1 | 1 | HRC-I | NONE | N | Sep 6 2022 11:33AM |
Leo I | ACTIVE GALAXIES AND QUASARS | Pacucci | 80 | 30 | ACIS-S | NONE | D | Aug 24 2022 12:40PM |
GRB 220706A | SN, SNR AND ISOLATED NS | Gompertz | 15 | 15 | ACIS-S | NONE | N | Aug 9 2022 12:18PM |
DQ Tau | STARS AND WD | Getman | 18 | 18 | ACIS-I | NONE | N | Jul 15 2022 4:38PM |
GRB220611A | SN, SNR AND ISOLATED NS | Levan | 15 | 15 | ACIS-S | NONE | N | Jun 15 2022 10:24AM |
IGRJ17091-3624 | BH AND NS BINARIES | Wang | 30 | 30 | ACIS-S | HETG | D | Jun 2 2022 10:54AM |
Swift J095520.7+690400.9 | BH AND NS BINARIES | Brightman | 10 | 10 | ACIS-S | NONE | N | May 6 2022 1:53PM |
GRB 220412B | BH AND NS BINARIES | Gompertz | 40 | 40 | ACIS-S | NONE | D | Apr 26 2022 11:11AM |
Wolf 359 | STARS AND WD | Howard | 36 | 36 | ACIS-S | HETG | N | Mar 22 2022 11:12PM |
AT 2018hyz | ACTIVE GALAXIES AND QUASARS | Cendes | 15 | 15 | ACIS-S | NONE | D | Feb 17 2022 12:09PM |
SDSS J143016.05+230344.4 | ACTIVE GALAXIES AND QUASARS | Jiang | 250 | 60 | ACIS-S | NONE | 1 | Jan 29 2022 10:46AM |
SGRB211106A | BH AND NS BINARIES | Rouco Escorial | 40 | 40 | ACIS-S | NONE | D | Dec 20 2021 12:32PM |
SGRB 210726A | BH AND NS BINARIES | Schroeder | 40 | 40 | ACIS-S | NONE | D | Dec 9 2021 2:41PM |
47 Tuc | BH AND NS BINARIES | Paduano | 20 | 20 | ACIS-S | NONE | N | Nov 24 2021 3:18AM |
GLEAM-X J162759.5-523504.3 | SN, SNR AND ISOLATED NS | Hurley-Walker | 30 | 30 | ACIS-S | NONE | D | Nov 22 2021 6:31AM |
GRB210905A | SN, SNR AND ISOLATED NS | MARGUTTI | 20 | 20 | ACIS-S | NONE | N | Nov 3 2021 12:46PM |
IC 10 X-1 | BH AND NS BINARIES | Binder | 30 | 30 | ACIS-S | NONE | N | Oct 21 2021 4:38PM |
ERO_TDE_1 | ACTIVE GALAXIES AND QUASARS | Malyali | 30 | 30 | HRC-I | NONE | D | Oct 20 2021 5:38PM |
SN 2021aabp | SN, SNR AND ISOLATED NS | Ho | 20 | 20 | ACIS-S | NONE | D | Oct 8 2021 10:47AM |
EXO 2030+375 | BH AND NS BINARIES | Pradhan | 30 | 10 | ACIS-S | HETG | D | Sep 10 2021 10:42AM |
Cycle | Sequence Number | ObsID | Instrument | Grating | Approved Exposure Time | Actual Exposure Time | Target | Status | Approval Date | Start Time [UT] | Proprietary Time | PI Name |
---|---|---|---|---|---|---|---|---|---|---|---|---|
25 | 503585 | 30557 | ACIS-S | NONE | 50.000000 | 0.000000 | DIRECTV7984M31B | unobserved | Sep 30 2024 9:11AM | D | De | |
25 | 705195 | 29490 | ACIS-S | HETG | 22.000000 | 20.663821 | CenA | archived | Jul 16 2024 9:27AM | Aug 7 2024 7:19AM | N | Bogensberger |
25 | 201740 | 29420 | ACIS-S | NONE | 10.000000 | 10.881000 | EP240414a | archived | May 16 2024 8:35AM | Jun 16 2024 5:53AM | N | Jonker |
25 | 402525 | 29396 | ACIS-S | NONE | 10.000000 | 10.084704 | GaiaBH3 | archived | Apr 21 2024 6:14PM | May 25 2024 1:59AM | N | Pacucci |
25 | 503516 | 29384 | ACIS-S | NONE | 15.000000 | 14.784000 | SN2024ggi | archived | Apr 13 2024 6:00PM | Apr 27 2024 12:01AM | D | Zimmerman |
25 | 503515 | 29383 | ACIS-S | NONE | 15.000000 | 15.084000 | SN2024ggi | archived | Apr 13 2024 6:00PM | Apr 21 2024 4:57PM | D | Zimmerman |
25 | 300555 | 29382 | ACIS-S | HETG | 30.000000 | 30.059200 | V1723Sco | archived | Apr 12 2024 4:42PM | May 7 2024 7:56AM | N | Sokolovsky |
25 | 503514 | 29380 | ACIS-S | NONE | 15.000000 | 16.583645 | LXT240402a | archived | Apr 11 2024 6:58PM | Apr 15 2024 12:48AM | D | Troja |
25 | 705176 | 29356 | HRC-I | NONE | 2.000000 | 2.002081 | EP240222a | archived | Mar 26 2024 8:55AM | Apr 1 2024 2:34PM | D | Jin |
25 | 705175 | 29355 | ACIS-S | NONE | 2.000000 | 2.067700 | ZTF19acnskyy | archived | Mar 25 2024 9:15AM | Apr 3 2024 7:05PM | D | Hernandez-Garcia |
25 | 201735 | 29353 | ACIS-S | NONE | 20.000000 | 18.786000 | EP240315A | archived | Mar 17 2024 3:48PM | Mar 26 2024 4:56AM | N | Levan |
25 | 201734 | 29352 | ACIS-S | NONE | 10.000000 | 10.082695 | EP240315A | archived | Mar 17 2024 3:48PM | Mar 18 2024 8:13PM | N | Levan |
25 | 402524 | 29351 | ACIS-S | NONE | 19.000000 | 18.383230 | A0620-00 | archived | Mar 15 2024 4:11PM | Mar 27 2024 9:35PM | N | Gallo |
25 | 402524 | 29332 | ACIS-S | NONE | 17.000000 | 17.751000 | A0620-00 | archived | Mar 7 2024 1:56PM | Mar 26 2024 1:42PM | N | Gallo |
25 | 402523 | 29318 | HRC-I | NONE | 5.000000 | 5.003282 | SRGAJ144459.2-60420 | archived | Mar 1 2024 4:30PM | Mar 6 2024 11:14AM | N | Illiano |
25 | 503513 | 29317 | ACIS-S | NONE | 20.000000 | 20.080859 | GRB240218A | archived | Feb 28 2024 4:01PM | Mar 4 2024 11:23PM | N | Pena |
25 | 201730 | 29316 | ACIS-S | HETG | 10.000000 | 9.557300 | HR1099 | archived | Feb 26 2024 2:44PM | Mar 9 2024 9:32AM | N | Miller |
25 | 201730 | 29315 | ACIS-S | HETG | 10.000000 | 10.059032 | HR1099 | archived | Feb 26 2024 2:44PM | Mar 9 2024 2:18AM | N | Miller |
25 | 201730 | 29278 | ACIS-S | HETG | 10.000000 | 10.561700 | HR1099 | archived | Feb 6 2024 4:24PM | Mar 8 2024 6:22PM | N | Miller |
24 | 705150 | 29180 | ACIS-S | HETG | 44.000000 | 42.563000 | NGC4151 | archived | Dec 19 2023 6:44PM | Dec 27 2023 9:45PM | D | Miller |
24 | 705150 | 29179 | ACIS-S | HETG | 18.000000 | 17.612800 | NGC4151 | archived | Dec 19 2023 6:44PM | Dec 26 2023 12:31PM | D | Miller |
24 | 705150 | 29137 | ACIS-S | HETG | 38.000000 | 37.367400 | NGC4151 | archived | Dec 14 2023 7:45AM | Dec 25 2023 2:06PM | D | Miller |
24 | 705140 | 29072 | ACIS-S | NONE | 10.000000 | 10.093945 | NGC1068 | archived | Nov 7 2023 12:41PM | Jan 28 2024 5:56PM | N | Marinucci |
24 | 705139 | 29071 | ACIS-S | NONE | 10.000000 | 11.094365 | NGC1068 | archived | Nov 7 2023 12:41PM | Jan 4 2024 5:57PM | N | Marinucci |
24 | 705136 | 29069 | ACIS-S | NONE | 15.000000 | 14.483370 | HE0230-2130 | archived | Nov 6 2023 5:03PM | Nov 17 2023 2:07PM | N | Pooley |
24 | 402522 | 29059 | ACIS-S | HETG | 20.000000 | 18.961000 | CygX-3 | archived | Nov 6 2023 9:10AM | Nov 22 2023 8:10PM | N | McCollough |
24 | 705138 | 29040 | ACIS-S | NONE | 30.000000 | 28.086000 | HE0230-2130 | archived | Oct 31 2023 2:38PM | Dec 2 2023 12:31AM | N | Pooley |
24 | 705137 | 29039 | ACIS-S | NONE | 30.000000 | 30.083682 | HE0230-2130 | archived | Oct 31 2023 2:38PM | Nov 25 2023 12:34PM | N | Pooley |
24 | 705136 | 29038 | ACIS-S | NONE | 15.000000 | 14.735231 | HE0230-2130 | archived | Oct 31 2023 2:38PM | Nov 14 2023 4:58AM | N | Pooley |
24 | 705135 | 29037 | ACIS-S | NONE | 30.000000 | 30.110455 | HE0230-2130 | archived | Oct 31 2023 2:38PM | Nov 8 2023 6:15PM | N | Pooley |
24 | 503512 | 29036 | ACIS-S | NONE | 13.000000 | 12.166381 | AT2023uqf | archived | Oct 26 2023 11:29AM | Oct 30 2023 6:26AM | D | Stein |
24 | 503512 | 29035 | ACIS-S | NONE | 12.000000 | 11.730400 | AT2023uqf | archived | Oct 25 2023 9:24PM | Oct 29 2023 9:11AM | D | Stein |
24 | 402519 | 28927 | ACIS-S | NONE | 15.000000 | 15.091000 | V404Cyg | archived | Sep 15 2023 9:47AM | Oct 14 2023 8:30PM | N | Hynes |
24 | 402518 | 28925 | ACIS-S | NONE | 14.000000 | 14.074000 | GRB230812B | archived | Sep 11 2023 11:55AM | Sep 23 2023 1:05AM | D | Pathak |
24 | 402518 | 28868 | ACIS-S | NONE | 16.000000 | 15.074830 | GRB230812B | archived | Aug 21 2023 1:06PM | Sep 18 2023 8:03PM | D | Pathak |
24 | 402517 | 28867 | ACIS-S | NONE | 20.000000 | 21.675200 | GRB230812B | archived | Aug 21 2023 1:06PM | Sep 3 2023 1:24AM | D | Pathak |
24 | 503452 | 28374 | ACIS-S | NONE | 9.500000 | 10.019200 | SN2023ixf | archived | Jul 28 2023 2:50PM | Aug 12 2023 12:28PM | D | Chandra |
24 | 402459 | 28366 | ACIS-S | HETG | 14.000000 | 14.846100 | 4U1626-67 | archived | Jul 27 2023 6:14PM | Jul 31 2023 1:33PM | N | Ng |
24 | 402459 | 27960 | ACIS-S | HETG | 16.000000 | 16.547321 | 4U1626-67 | archived | Jul 13 2023 5:56PM | Jul 31 2023 3:15AM | N | Ng |
24 | 402459 | 27954 | ACIS-S | HETG | 30.000000 | 30.045062 | 4U1626-67 | archived | Jul 7 2023 3:44PM | Jul 29 2023 3:14PM | N | Ng |
24 | 704945 | 27953 | ACIS-S | NONE | 25.000000 | 23.081609 | AT2021lwx | archived | Jul 6 2023 6:14PM | Nov 18 2023 3:29PM | N | Guolo |
24 | 503453 | 27933 | ACIS-S | NONE | 20.000000 | 19.083000 | AT2023lcr | archived | Jun 26 2023 2:51PM | Jul 3 2023 6:47AM | D | Martin-Carrillo |
24 | 100228 | 27882 | ACIS-S | NONE | 29.900000 | 31.103999 | LTT1445A | archived | May 26 2023 10:30AM | Aug 2 2023 11:33PM | N | Howard |
24 | 503452 | 27863 | ACIS-S | NONE | 10.500000 | 11.183205 | SN2023ixf | archived | May 22 2023 8:56AM | Aug 11 2023 6:38PM | D | Chandra |
24 | 503451 | 27862 | ACIS-S | NONE | 20.000000 | 20.332900 | SN2023ixf | archived | May 22 2023 8:56AM | May 31 2023 3:51PM | D | Chandra |
24 | 704913 | 27798 | ACIS-S | NONE | 10.000000 | 10.082037 | WISEAJ045649.8-2037 | archived | Apr 3 2023 9:02AM | Apr 14 2023 3:51AM | D | Liu |
24 | 402458 | 27779 | ACIS-S | NONE | 14.000000 | 13.783673 | GRB230307A | archived | Mar 22 2023 4:23PM | Apr 2 2023 10:13AM | N | Fong |
24 | 402458 | 27778 | ACIS-S | NONE | 17.000000 | 17.082000 | GRB230307A | archived | Mar 22 2023 4:22PM | Apr 1 2023 9:57PM | N | Fong |
24 | 402458 | 27777 | ACIS-S | NONE | 19.000000 | 20.082000 | GRB230307A | archived | Mar 22 2023 10:50AM | Mar 31 2023 10:36AM | N | Fong |
24 | 704913 | 27738 | ACIS-S | NONE | 10.000000 | 10.193522 | WISEAJ045649.8-2037 | archived | Mar 2 2023 1:47PM | Apr 11 2023 12:43AM | D | Liu |
24 | 704912 | 27737 | ACIS-S | NONE | 10.000000 | 10.083000 | WISEAJ045649.8-2037 | archived | Mar 2 2023 1:47PM | Mar 19 2023 10:37PM | D | Liu |
24 | 402457 | 27736 | ACIS-S | NONE | 10.000000 | 11.097900 | Terzan5 | archived | Mar 1 2023 4:58PM | Mar 18 2023 3:10PM | N | Heinke |
24 | 402456 | 27707 | ACIS-S | HETG | 20.000000 | 19.916332 | RXJ0440.9+4431 | archived | Feb 1 2023 4:55PM | Feb 13 2023 7:36AM | D | Reynolds |
23 | 503450 | 27646 | ACIS-S | NONE | 10.000000 | 10.059500 | SN2022jli | archived | Dec 23 2022 10:23AM | Jan 25 2023 9:34PM | N | Chen |
23 | 503449 | 27645 | ACIS-S | NONE | 10.000000 | 10.059500 | SN2022jli | archived | Dec 23 2022 10:23AM | Jan 21 2023 11:00PM | N | Chen |
23 | 503448 | 27644 | ACIS-S | NONE | 10.000000 | 10.062600 | SN2022jli | archived | Dec 23 2022 10:23AM | Jan 17 2023 11:05AM | N | Chen |
23 | 503444 | 27643 | ACIS-S | NONE | 16.000000 | 15.344835 | AT2022tsd | archived | Dec 21 2022 11:47AM | Dec 29 2022 7:27AM | N | Ho |
23 | 503444 | 27639 | ACIS-S | NONE | 24.000000 | 22.940584 | AT2022tsd | archived | Dec 20 2022 4:41PM | Dec 26 2022 2:32PM | N | Ho |
23 | 201611 | 27638 | ACIS-S | NONE | 20.000000 | 18.582000 | GaiaJ1350-5914 | archived | Dec 19 2022 4:18PM | Jan 25 2023 9:41AM | D | El-Badry |
23 | 402454 | 27524 | ACIS-S | NONE | 10.000000 | 10.080000 | GaiaBH1 | archived | Oct 25 2022 12:09PM | Oct 31 2022 1:53AM | D | Rodriguez |
23 | 901855 | 27517 | ACIS-I | NONE | 20.000000 | 22.031700 | SwiftJ1913.1+1946 | archived | Oct 12 2022 1:30PM | Oct 17 2022 5:13PM | D | Heinz |
23 | 704875 | 27483 | ACIS-S | NONE | 10.000000 | 10.945828 | DECALS2157-4201 | archived | Oct 7 2022 10:06AM | Nov 25 2022 9:50PM | D | Pooley |
23 | 402454 | 27482 | ACIS-S | NONE | 10.000000 | 9.899936 | GaiaBH1 | archived | Oct 5 2022 4:44PM | Oct 30 2022 5:14PM | D | Rodriguez |
23 | 402453 | 27481 | ACIS-S | NONE | 10.000000 | 10.086000 | NGC7793 | archived | Oct 4 2022 9:07AM | Oct 27 2022 2:21PM | N | Brightman |
23 | 704863 | 27480 | ACIS-S | NONE | 12.000000 | 12.569367 | LeoI | archived | Oct 3 2022 3:09PM | Oct 15 2022 6:25AM | D | Pacucci |
23 | 704871 | 27470 | ACIS-S | NONE | 3.000000 | 2.906434 | SwiftJ023017.0+2836 | archived | Sep 23 2022 9:21AM | Sep 27 2022 10:26PM | D | Evans |
23 | 100227 | 27452 | HRC-S | NONE | 10.000000 | 9.914057 | TIC420112589 | archived | Sep 13 2022 9:49AM | Apr 10 2023 7:12AM | D | Poppenhaeger |
23 | 402452 | 27444 | ACIS-S | NONE | 3.000000 | 3.097800 | SwiftJ174038.1-2737 | archived | Sep 9 2022 11:28AM | Oct 12 2022 2:40PM | N | Maccarone |
23 | 704863 | 27442 | ACIS-S | NONE | 18.000000 | 19.240800 | LeoI | archived | Sep 6 2022 4:34PM | Oct 14 2022 7:34PM | D | Pacucci |
23 | 503440 | 27263 | ACIS-S | NONE | 15.000000 | 15.021000 | GRB220706A | archived | Aug 10 2022 9:03AM | Aug 16 2022 1:06PM | N | Gompertz |
23 | 201554 | 26475 | ACIS-I | NONE | 1.500000 | 1.602000 | DQTau | archived | Jul 15 2022 5:18PM | Aug 13 2022 5:11PM | N | Getman |
23 | 201553 | 26474 | ACIS-I | NONE | 1.500000 | 1.616402 | DQTau | archived | Jul 15 2022 5:18PM | Aug 11 2022 5:47AM | N | Getman |
23 | 201552 | 26473 | ACIS-I | NONE | 1.500000 | 1.602000 | DQTau | archived | Jul 15 2022 5:18PM | Aug 10 2022 1:47PM | N | Getman |
23 | 201551 | 26472 | ACIS-I | NONE | 1.500000 | 1.601909 | DQTau | archived | Jul 15 2022 5:18PM | Aug 9 2022 4:22PM | N | Getman |
23 | 201550 | 26471 | ACIS-I | NONE | 1.500000 | 1.572000 | DQTau | archived | Jul 15 2022 5:18PM | Aug 8 2022 4:24PM | N | Getman |
23 | 201549 | 26470 | ACIS-I | NONE | 1.500000 | 1.602500 | DQTau | archived | Jul 15 2022 5:18PM | Aug 7 2022 1:05PM | N | Getman |
23 | 201548 | 26469 | ACIS-I | NONE | 1.500000 | 1.602873 | DQTau | archived | Jul 15 2022 5:18PM | Aug 6 2022 3:03PM | N | Getman |
23 | 201547 | 26468 | ACIS-I | NONE | 1.500000 | 1.601858 | DQTau | archived | Jul 15 2022 5:18PM | Aug 5 2022 12:20PM | N | Getman |
23 | 201546 | 26467 | ACIS-I | NONE | 1.500000 | 1.601500 | DQTau | archived | Jul 15 2022 5:18PM | Aug 4 2022 11:22AM | N | Getman |
23 | 201545 | 26466 | ACIS-I | NONE | 1.500000 | 1.602000 | DQTau | archived | Jul 15 2022 5:18PM | Aug 3 2022 5:56AM | N | Getman |
23 | 201544 | 26465 | ACIS-I | NONE | 1.500000 | 1.602000 | DQTau | archived | Jul 15 2022 5:18PM | Aug 2 2022 5:55AM | N | Getman |
23 | 201543 | 26464 | ACIS-I | NONE | 1.500000 | 1.602989 | DQTau | archived | Jul 15 2022 5:18PM | Aug 1 2022 7:31AM | N | Getman |
23 | 503371 | 26441 | ACIS-S | NONE | 15.000000 | 15.080647 | GRB220611A | archived | Jun 15 2022 7:22PM | Jun 23 2022 11:57PM | N | Levan |
23 | 402361 | 26435 | ACIS-S | HETG | 30.000000 | 30.080045 | IGRJ17091-3624 | archived | Jun 2 2022 12:12PM | Jun 16 2022 11:42AM | D | Wang |
23 | 402360 | 26421 | ACIS-S | NONE | 10.000000 | 10.082040 | SwiftJ095520.7+6904 | archived | May 11 2022 9:13AM | Jun 4 2022 11:51AM | N | Brightman |
23 | 402359 | 26407 | ACIS-S | NONE | 40.000000 | 40.102883 | GRB220412B | archived | Apr 27 2022 12:42PM | May 2 2022 7:25AM | D | Gompertz |
23 | 201530 | 26388 | ACIS-S | HETG | 12.000000 | 11.954300 | Wolf359 | archived | Apr 1 2022 7:18PM | Jul 1 2022 8:05PM | N | Howard |
23 | 201529 | 26387 | ACIS-S | HETG | 12.000000 | 11.950853 | Wolf359 | archived | Apr 1 2022 7:18PM | Jun 30 2022 7:50PM | N | Howard |
23 | 201528 | 26386 | ACIS-S | HETG | 12.000000 | 11.059200 | Wolf359 | archived | Apr 1 2022 7:18PM | Jun 28 2022 10:49PM | N | Howard |
23 | 704610 | 26350 | ACIS-S | NONE | 15.000000 | 15.080562 | AT2018hyz | archived | Feb 24 2022 1:38PM | Mar 19 2022 11:12AM | D | Cendes |
23 | 704603 | 26330 | ACIS-S | NONE | 4.000000 | 4.204800 | SDSSJ143016.05+2303 | archived | Feb 7 2022 3:41PM | Mar 16 2022 6:02PM | 1 | Jiang |
23 | 704603 | 26329 | ACIS-S | NONE | 4.000000 | 4.104715 | SDSSJ143016.05+2303 | archived | Feb 7 2022 3:41PM | Mar 16 2022 1:23AM | 1 | Jiang |
23 | 704603 | 26328 | ACIS-S | NONE | 4.000000 | 4.149000 | SDSSJ143016.05+2303 | archived | Feb 7 2022 3:41PM | Mar 14 2022 4:11AM | 1 | Jiang |
23 | 704603 | 26327 | ACIS-S | NONE | 4.000000 | 4.104000 | SDSSJ143016.05+2303 | archived | Feb 7 2022 3:41PM | Mar 13 2022 8:17AM | 1 | Jiang |
23 | 704603 | 26326 | ACIS-S | NONE | 4.000000 | 4.092500 | SDSSJ143016.05+2303 | archived | Feb 7 2022 3:41PM | Mar 11 2022 2:49PM | 1 | Jiang |
23 | 704603 | 26325 | ACIS-S | NONE | 4.000000 | 4.089988 | SDSSJ143016.05+2303 | archived | Feb 7 2022 3:41PM | Mar 9 2022 1:12PM | 1 | Jiang |
23 | 704603 | 26324 | ACIS-S | NONE | 4.000000 | 4.091500 | SDSSJ143016.05+2303 | archived | Feb 7 2022 3:41PM | Mar 7 2022 11:50PM | 1 | Jiang |
23 | 704603 | 26323 | ACIS-S | NONE | 4.000000 | 4.090758 | SDSSJ143016.05+2303 | archived | Feb 7 2022 3:41PM | Mar 6 2022 10:09AM | 1 | Jiang |
23 | 704603 | 26322 | ACIS-S | NONE | 4.000000 | 4.091000 | SDSSJ143016.05+2303 | archived | Feb 7 2022 3:41PM | Mar 3 2022 11:01PM | 1 | Jiang |
23 | 704603 | 26321 | ACIS-S | NONE | 4.000000 | 4.091870 | SDSSJ143016.05+2303 | archived | Feb 7 2022 3:41PM | Mar 2 2022 9:54AM | 1 | Jiang |
23 | 704603 | 26320 | ACIS-S | NONE | 4.000000 | 4.092000 | SDSSJ143016.05+2303 | archived | Feb 7 2022 3:41PM | Feb 28 2022 9:51PM | 1 | Jiang |
23 | 704603 | 26319 | ACIS-S | NONE | 4.000000 | 4.091383 | SDSSJ143016.05+2303 | archived | Feb 7 2022 3:41PM | Feb 27 2022 7:31AM | 1 | Jiang |
23 | 704603 | 26318 | ACIS-S | NONE | 4.000000 | 4.091000 | SDSSJ143016.05+2303 | archived | Feb 7 2022 3:41PM | Feb 25 2022 4:13AM | 1 | Jiang |
23 | 704603 | 26317 | ACIS-S | NONE | 4.000000 | 4.091500 | SDSSJ143016.05+2303 | archived | Feb 7 2022 3:41PM | Feb 23 2022 1:27AM | 1 | Jiang |
23 | 704603 | 26316 | ACIS-S | NONE | 4.000000 | 4.090000 | SDSSJ143016.05+2303 | archived | Feb 7 2022 2:39PM | Feb 21 2022 3:46AM | 1 | Jiang |
22 | 402355 | 26286 | ACIS-S | NONE | 10.000000 | 9.959991 | 47Tuc | archived | Jan 14 2022 12:19PM | Jan 27 2022 2:32AM | N | Paduano |
22 | 503370 | 26282 | ACIS-S | NONE | 10.000000 | 10.111420 | GLEAM-XJ162759.5-52 | archived | Jan 10 2022 12:17PM | Jan 23 2022 6:25AM | D | Hurley-Walker |
22 | 402357 | 26262 | ACIS-S | NONE | 19.000000 | 18.463645 | SGRB211106A | archived | Dec 21 2021 12:13PM | Jan 5 2022 3:49AM | D | RoucoEscorial |
22 | 402357 | 26249 | ACIS-S | NONE | 21.000000 | 19.962000 | SGRB211106A | archived | Dec 20 2021 12:41PM | Jan 4 2022 3:21PM | D | RoucoEscorial |
22 | 402356 | 26247 | ACIS-S | NONE | 40.000000 | 36.753000 | SGRB210726A | archived | Dec 13 2021 10:50AM | Dec 31 2021 7:10PM | D | Schroeder |
22 | 402355 | 26229 | ACIS-S | NONE | 10.000000 | 9.780000 | 47Tuc | archived | Dec 6 2021 9:08AM | Jan 26 2022 3:48PM | N | Paduano |
22 | 503370 | 26228 | ACIS-S | NONE | 20.000000 | 20.090522 | GLEAM-XJ162759.5-52 | archived | Nov 26 2021 1:53PM | Jan 22 2022 9:13PM | D | Hurley-Walker |
22 | 503369 | 26205 | ACIS-S | NONE | 20.000000 | 19.409637 | GRB210905A | archived | Nov 4 2021 12:17PM | Nov 24 2021 1:28PM | N | MARGUTTI |
22 | 704586 | 26189 | HRC-I | NONE | 30.000000 | 30.123471 | ERO_TDE_1 | archived | Oct 28 2021 11:41AM | Nov 10 2021 11:50PM | D | Malyali |
22 | 402354 | 26188 | ACIS-S | NONE | 30.000000 | 30.073100 | IC10X-1 | archived | Oct 28 2021 11:04AM | Jan 7 2022 6:26AM | N | Binder |
22 | 503368 | 26159 | ACIS-S | NONE | 20.000000 | 19.889600 | SN2021aabp | archived | Oct 8 2021 12:28PM | Oct 15 2021 8:05AM | D | Ho |
22 | 402353 | 26154 | ACIS-S | HETG | 10.000000 | 10.080000 | EXO2030+375 | archived | Sep 30 2021 5:15PM | Oct 20 2021 3:43AM | D | Pradhan |
22 | 503296 | 25093 | ACIS-S | NONE | 20.000000 | 20.090218 | GRB210704A | archived | Jul 13 2021 9:05AM | Jul 19 2021 1:50AM | D | Troja |
22 | 300502 | 25092 | HRC-S | LETG | 30.000000 | 30.040830 | V1674Her | archived | Jul 12 2021 9:04AM | Jul 19 2021 7:59AM | N | Drake |
22 | 300501 | 25089 | HRC-S | NONE | 10.000000 | 10.134432 | TCPJ18573095+165339 | archived | Jul 3 2021 5:11PM | Jul 10 2021 1:30AM | N | Maccarone |
22 | 402298 | 25079 | ACIS-S | HETG | 30.000000 | 28.058000 | 4U1543-475 | archived | Jun 13 2021 1:38PM | Jun 21 2021 9:23AM | N | Miller |
22 | 503295 | 25064 | ACIS-S | NONE | 19.000000 | 18.288000 | AT2020mrf | archived | Jun 7 2021 11:20AM | Jun 19 2021 8:21AM | N | Yao |
22 | 402296 | 25063 | ACIS-S | HETG | 12.500000 | 12.625000 | MAXIJ1803-298 | archived | Jun 7 2021 11:19AM | Jun 18 2021 5:21AM | D | DiazTrigo |
22 | 704293 | 25060 | HRC-S | LETG | 28.000000 | 28.038000 | AT2019avd | archived | Jun 2 2021 12:05PM | Jun 9 2021 8:08PM | N | Pasham |
22 | 704293 | 25056 | HRC-S | LETG | 22.000000 | 21.877601 | AT2019avd | archived | May 31 2021 3:16PM | Jun 8 2021 4:49PM | N | Pasham |
22 | 402297 | 25054 | ACIS-S | NONE | 30.000000 | 29.947334 | MAXIJ1348-630 | archived | May 14 2021 4:32PM | Jun 28 2021 6:01AM | D | Carotenuto |
22 | 503295 | 25050 | ACIS-S | NONE | 21.000000 | 20.091000 | AT2020mrf | archived | May 13 2021 10:36AM | Jun 18 2021 10:29AM | N | Yao |
22 | 503294 | 25049 | ACIS-S | NONE | 60.000000 | 60.053200 | CXOJ134856.4+263944 | archived | May 12 2021 9:33AM | Jun 2 2021 11:43PM | D | Lin |
22 | 402296 | 25041 | ACIS-S | HETG | 12.500000 | 12.627000 | MAXIJ1803-298 | archived | May 10 2021 11:29AM | Jun 17 2021 8:29PM | D | DiazTrigo |
22 | 402295 | 25040 | ACIS-S | HETG | 25.000000 | 23.700000 | MAXIJ1803-298 | archived | May 10 2021 11:29AM | May 23 2021 7:30PM | D | DiazTrigo |
22 | 402294 | 25039 | ACIS-S | HETG | 25.000000 | 25.100000 | MAXIJ1803-298 | archived | May 10 2021 11:29AM | May 17 2021 9:15AM | D | DiazTrigo |
22 | 704292 | 25025 | ACIS-S | HETG | 50.000000 | 50.079943 | NGC4151 | archived | Apr 23 2021 9:46AM | May 3 2021 10:37AM | D | Miller |
22 | 503293 | 25016 | ACIS-S | NONE | 30.000000 | 30.066227 | FRB20201124A | archived | Apr 16 2021 12:40PM | Apr 20 2021 5:28AM | D | Piro |
22 | 503292 | 25005 | HRC-I | NONE | 2.000000 | 2.180175 | ASASSN-20hx | archived | Mar 30 2021 2:15PM | Apr 16 2021 7:35AM | N | Mandal |
22 | 402293 | 24986 | ACIS-S | NONE | 10.000000 | 10.091968 | SwiftJ130456-493158 | archived | Mar 4 2021 2:05PM | Mar 10 2021 4:06AM | N | Brightman |
22 | 503291 | 24966 | ACIS-S | NONE | 25.000000 | 25.070248 | ASKAPJ173608.2-3216 | archived | Feb 12 2021 11:16AM | Feb 17 2021 2:51PM | N | Kaplan |
22 | 503290 | 24965 | ACIS-S | NONE | 25.000000 | 24.590441 | GRB190610A | archived | Feb 8 2021 10:52AM | Feb 26 2021 7:53AM | N | Tohuvavohu |
21 | 704287 | 24911 | ACIS-S | NONE | 15.000000 | 15.069599 | PKS1127-14 | archived | Dec 18 2020 9:28AM | Jan 1 2021 7:34PM | D | Siemiginowska |
21 | 503289 | 24910 | ACIS-S | NONE | 25.000000 | 25.317039 | GRB201214B | archived | Dec 16 2020 5:27PM | Jan 11 2021 2:29PM | D | Troja |
21 | 503288 | 24909 | ACIS-S | NONE | 25.000000 | 25.054200 | GRB201214B | archived | Dec 16 2020 5:27PM | Dec 22 2020 5:35PM | D | Troja |
21 | 704286 | 24876 | ACIS-S | NONE | 30.000000 | 29.059377 | ESO253-G003 | archived | Nov 18 2020 2:02PM | Jan 21 2021 8:11PM | D | Payne |
21 | 704285 | 24875 | ACIS-S | NONE | 30.000000 | 28.061200 | ESO253-G003 | archived | Nov 18 2020 2:02PM | Dec 26 2020 12:11PM | D | Payne |
21 | 100204 | 24847 | HRC-I | NONE | 10.000000 | 10.006307 | Saturn | archived | Oct 19 2020 8:53AM | Nov 23 2020 11:01PM | N | Weigt |
21 | 100204 | 24846 | HRC-I | NONE | 10.000000 | 10.136482 | Saturn | archived | Oct 19 2020 8:53AM | Nov 21 2020 12:31PM | N | Weigt |
21 | 100204 | 24845 | HRC-I | NONE | 10.000000 | 10.125976 | Saturn | archived | Oct 19 2020 8:46AM | Nov 19 2020 11:48AM | N | Weigt |
21 | 503287 | 24841 | ACIS-S | NONE | 5.000000 | 5.078000 | SGR1830-0645 | archived | Oct 10 2020 4:38PM | Oct 13 2020 9:51PM | N | Kouveliotou |
21 | 704283 | 24755 | ACIS-S | NONE | 30.000000 | 30.060798 | RXJ1756.4+5235 | archived | Sep 28 2020 3:41AM | Nov 5 2020 4:02AM | N | Koss |
21 | 704254 | 24667 | ACIS-S | HETG | 23.000000 | 22.639115 | Mrk279 | archived | Sep 21 2020 4:16PM | Oct 3 2020 4:09AM | D | Miller |
21 | 704254 | 24666 | ACIS-S | HETG | 23.000000 | 22.943727 | Mrk279 | archived | Sep 21 2020 4:16PM | Sep 30 2020 8:08AM | D | Miller |
21 | 704254 | 24665 | ACIS-S | HETG | 23.000000 | 22.943436 | Mrk279 | archived | Sep 21 2020 4:16PM | Sep 29 2020 1:43PM | D | Miller |
21 | 704254 | 24662 | ACIS-S | HETG | 31.000000 | 31.884800 | Mrk279 | archived | Sep 16 2020 7:18AM | Sep 28 2020 4:18PM | D | Miller |
21 | 402282 | 24651 | ACIS-S | HETG | 25.000000 | 25.070399 | AT2019wey/SRG | archived | Sep 9 2020 12:18PM | Sep 20 2020 5:59PM | N | Kulkarni |
21 | 704251 | 24640 | ACIS-S | NONE | 20.000000 | 20.056783 | 2MASXJ01110461-4558 | archived | Aug 24 2020 5:43AM | Sep 16 2020 4:12PM | D | Lin |
21 | 503278 | 24619 | ACIS-S | NONE | 30.000000 | 30.054932 | PSRJ1846-0258 | archived | Aug 13 2020 3:35PM | Sep 15 2020 10:39AM | N | Blumer |
21 | 402198 | 23360 | ACIS-S | HETG | 15.000000 | 15.078000 | herculesx-1 | archived | Jul 31 2020 9:39AM | Aug 14 2020 10:05PM | D | Kosec |
21 | 402198 | 23356 | ACIS-S | HETG | 35.000000 | 35.077750 | herculesx-1 | archived | Jul 20 2020 9:03AM | Aug 12 2020 5:43AM | D | Kosec |
21 | 503207 | 23331 | ACIS-S | NONE | 10.000000 | 10.092000 | SN2012au | archived | Jul 9 2020 1:37PM | Jul 20 2020 8:08AM | D | MARGUTTI |
21 | 503207 | 23316 | ACIS-S | NONE | 10.000000 | 9.912000 | SN2012au | archived | Jun 30 2020 3:19PM | Jul 19 2020 5:05PM | D | MARGUTTI |
21 | 503206 | 23315 | ACIS-S | NONE | 12.000000 | 12.356394 | SN2020nlb | archived | Jun 30 2020 10:17AM | Jul 12 2020 4:34AM | D | Sand |
21 | 503206 | 23314 | ACIS-S | NONE | 63.000000 | 62.680954 | SN2020nlb | archived | Jun 29 2020 3:06PM | Jul 10 2020 12:16AM | D | Sand |
21 | 704049 | 23300 | ACIS-S | HETG | 30.000000 | 30.077106 | Mrk335 | archived | Jun 22 2020 12:38PM | Jul 4 2020 2:17AM | N | Boissay-Malaquin |
21 | 704049 | 23299 | ACIS-S | HETG | 30.000000 | 30.079173 | Mrk335 | archived | Jun 22 2020 12:38PM | Jul 3 2020 8:29AM | N | Boissay-Malaquin |
21 | 704049 | 23298 | ACIS-S | HETG | 30.000000 | 30.079257 | Mrk335 | archived | Jun 22 2020 12:38PM | Jul 2 2020 2:15AM | N | Boissay-Malaquin |
21 | 704049 | 23297 | ACIS-S | HETG | 30.000000 | 30.076502 | Mrk335 | archived | Jun 22 2020 12:38PM | Jul 1 2020 9:25AM | N | Boissay-Malaquin |
21 | 704049 | 23292 | ACIS-S | HETG | 30.000000 | 30.080000 | Mrk335 | archived | Jun 19 2020 5:44PM | Jun 30 2020 4:41PM | N | Boissay-Malaquin |
21 | 704048 | 23289 | ACIS-S | NONE | 50.000000 | 47.409000 | AT2018fyk | archived | Jun 16 2020 10:25AM | Jun 29 2020 5:34AM | N | Wevers |
21 | 503205 | 23285 | ACIS-S | NONE | 20.000000 | 19.962000 | GRB190829A | archived | Jun 11 2020 11:03AM | Jun 29 2020 7:15PM | D | Troja |
21 | 402197 | 23266 | ACIS-S | NONE | 30.000000 | 30.092837 | NGC7793P13 | archived | May 11 2020 9:42AM | Jun 4 2020 4:57PM | N | Walton |
21 | 503204 | 23251 | ACIS-S | NONE | 20.000000 | 19.061460 | SGRJ1935+2154 | archived | May 6 2020 2:50PM | May 18 2020 11:04AM | D | Gogus |
21 | 100193 | 23232 | HRC-S | LETG | 3.300000 | 3.492431 | C/2019Y4ATLAS | archived | Apr 13 2020 2:44PM | Apr 28 2020 7:59PM | D | Bodewits |
21 | 100193 | 23231 | HRC-S | LETG | 3.300000 | 3.494481 | C/2019Y4ATLAS | archived | Apr 13 2020 2:44PM | Apr 28 2020 6:56PM | D | Bodewits |
21 | 100193 | 23230 | HRC-S | LETG | 3.300000 | 3.494481 | C/2019Y4ATLAS | archived | Apr 13 2020 2:44PM | Apr 28 2020 5:52PM | D | Bodewits |
21 | 100193 | 23229 | HRC-S | LETG | 3.300000 | 3.496531 | C/2019Y4ATLAS | archived | Apr 13 2020 2:44PM | Apr 28 2020 4:49PM | D | Bodewits |
21 | 100193 | 23228 | HRC-S | LETG | 3.300000 | 3.492431 | C/2019Y4ATLAS | archived | Apr 13 2020 2:44PM | Apr 28 2020 3:45PM | D | Bodewits |
21 | 100193 | 23227 | HRC-S | LETG | 3.300000 | 3.494481 | C/2019Y4ATLAS | archived | Apr 13 2020 2:44PM | Apr 28 2020 2:42PM | D | Bodewits |
21 | 100193 | 23226 | HRC-S | LETG | 3.300000 | 3.490125 | C/2019Y4ATLAS | archived | Apr 13 2020 2:44PM | Apr 28 2020 1:38PM | D | Bodewits |
21 | 100193 | 23225 | HRC-S | LETG | 3.300000 | 3.496531 | C/2019Y4ATLAS | archived | Apr 13 2020 2:44PM | Apr 28 2020 12:35PM | D | Bodewits |
21 | 100193 | 23224 | HRC-S | LETG | 3.600000 | 3.641056 | C/2019Y4ATLAS | archived | Apr 10 2020 5:52PM | Apr 28 2020 11:26AM | D | Bodewits |
21 | 503203 | 23209 | ACIS-S | NONE | 30.000000 | 30.059561 | J1818-1607 | archived | Mar 24 2020 1:50PM | Apr 3 2020 5:48AM | D | Blumer |
21 | 300469 | 23179 | ACIS-S | NONE | 25.000000 | 23.376000 | Haro1-10 | archived | Feb 19 2020 1:52PM | Jun 8 2020 5:13PM | D | Lucy |
21 | 300468 | 23178 | ACIS-S | NONE | 10.000000 | 9.849000 | IRAS15175-4508 | archived | Feb 19 2020 1:52PM | May 18 2020 5:30PM | D | Lucy |
21 | 503202 | 23172 | ACIS-S | NONE | 10.000000 | 10.050200 | SN2020bvc | archived | Feb 12 2020 5:07PM | Feb 29 2020 2:15AM | N | Ho |
21 | 503201 | 23171 | ACIS-S | NONE | 10.000000 | 10.055784 | SN2020bvc | archived | Feb 12 2020 5:07PM | Feb 16 2020 8:31PM | N | Ho |
21 | 201344 | 23148 | HRC-I | NONE | 5.000000 | 5.042232 | Betelgeuse | archived | Jan 29 2020 3:26PM | Aug 15 2020 11:56AM | N | Kashyap |
21 | 201343 | 23147 | HRC-I | NONE | 5.000000 | 5.159850 | Betelgeuse | archived | Jan 29 2020 3:26PM | Feb 17 2020 7:32PM | N | Kashyap |
21 | 503200 | 23141 | ACIS-S | NONE | 10.000000 | 10.090736 | SN2020oi | archived | Jan 21 2020 2:09PM | Mar 13 2020 9:53AM | D | Stroh |
21 | 503199 | 23140 | ACIS-S | NONE | 10.000000 | 10.090829 | SN2020oi | archived | Jan 21 2020 2:09PM | Feb 15 2020 1:25AM | D | Stroh |
21 | 503198 | 23133 | ACIS-S | NONE | 10.000000 | 10.058177 | SN2019yvq | archived | Jan 17 2020 10:42AM | Feb 6 2020 6:16AM | N | Pooley |
21 | 704036 | 23132 | ACIS-S | NONE | 5.000000 | 5.111237 | SDSSJ1539+3954 | archived | Jan 17 2020 10:38AM | Jun 18 2020 12:11AM | N | Ni |
20 | 402196 | 23116 | ACIS-S | NONE | 15.000000 | 15.056700 | 4FGLJ0336.0+7502 | archived | Dec 18 2019 2:37PM | Jan 25 2020 12:00PM | N | Li |
20 | 300467 | 23108 | ACIS-S | NONE | 50.000000 | 48.112000 | RAqr | archived | Dec 12 2019 4:50PM | Jan 12 2020 12:13AM | 3 | Karovska |
20 | 704032 | 23107 | ACIS-S | NONE | 25.000000 | 27.053700 | PSOJ047.4479+27.299 | archived | Dec 12 2019 1:34PM | Mar 24 2020 8:50PM | N | moretti |
20 | 402195 | 23106 | ACIS-S | NONE | 10.000000 | 9.945600 | NGC4045 | archived | Dec 10 2019 3:28PM | Dec 31 2019 6:11AM | N | Brightman |
20 | 100192 | 23093 | HRC-S | NONE | 12.500000 | 12.688476 | C/2019Q4Borisov | archived | Nov 27 2019 12:58PM | Dec 18 2019 6:49PM | N | Snios |
20 | 100192 | 23092 | HRC-S | NONE | 12.500000 | 12.662082 | C/2019Q4Borisov | archived | Nov 27 2019 12:58PM | Dec 18 2019 3:12PM | N | Snios |
20 | 100192 | 23091 | HRC-S | NONE | 12.500000 | 12.690782 | C/2019Q4Borisov | archived | Nov 27 2019 12:58PM | Dec 17 2019 1:39AM | N | Snios |
20 | 100192 | 23090 | HRC-S | NONE | 12.500000 | 12.655932 | C/2019Q4Borisov | archived | Nov 27 2019 12:58PM | Dec 16 2019 10:02PM | N | Snios |
20 | 100192 | 23089 | HRC-S | NONE | 12.500000 | 12.694882 | C/2019Q4Borisov | archived | Nov 27 2019 12:58PM | Dec 16 2019 8:02AM | N | Snios |
20 | 503197 | 23082 | ACIS-S | NONE | 18.000000 | 17.971999 | FRB180916.J0158+65 | archived | Nov 13 2019 4:46PM | Dec 18 2019 4:01AM | D | Scholz |
20 | 503197 | 23081 | ACIS-S | NONE | 18.000000 | 18.070654 | FRB180916.J0158+65 | archived | Nov 13 2019 4:25PM | Dec 3 2019 1:46AM | D | Scholz |
20 | 100192 | 22919 | HRC-S | NONE | 12.500000 | 12.534982 | C/2019Q4Borisov | archived | Oct 22 2019 3:16PM | Dec 16 2019 4:25AM | N | Snios |
20 | 704028 | 22918 | ACIS-S | NONE | 4.000000 | 4.062914 | PKS1413+135 | archived | Oct 18 2019 9:57AM | Jun 18 2020 11:00PM | N | Liodakis |
20 | 704028 | 22917 | ACIS-S | NONE | 4.000000 | 4.063425 | PKS1413+135 | archived | Oct 18 2019 9:57AM | May 4 2020 12:19AM | N | Liodakis |
20 | 704028 | 22916 | ACIS-S | NONE | 4.000000 | 4.061000 | PKS1413+135 | archived | Oct 18 2019 9:57AM | Mar 22 2020 5:28AM | N | Liodakis |
20 | 704028 | 22915 | ACIS-S | NONE | 4.000000 | 4.057900 | PKS1413+135 | archived | Oct 18 2019 9:57AM | Feb 3 2020 6:10PM | N | Liodakis |
20 | 704028 | 22914 | ACIS-S | NONE | 4.000000 | 4.064100 | PKS1413+135 | archived | Oct 18 2019 9:13AM | Dec 20 2019 11:30PM | N | Liodakis |
20 | 100191 | 22913 | ACIS-S | NONE | 1.000000 | 1.048585 | V1298Tau | archived | Oct 17 2019 8:23PM | Nov 17 2019 2:54PM | N | Poppenhaeger |
20 | 402194 | 22886 | ACIS-S | HETG | 30.000000 | 30.084319 | GRS1915+105 | archived | Oct 11 2019 4:19PM | Nov 30 2019 9:04AM | D | Miller |
20 | 402193 | 22885 | ACIS-S | HETG | 30.000000 | 30.044101 | GRS1915+105 | archived | Oct 11 2019 4:19PM | Nov 3 2019 9:08AM | D | Miller |
20 | 503196 | 22848 | ACIS-S | NONE | 20.000000 | 20.090037 | AT2019osy | archived | Sep 6 2019 2:00PM | Sep 22 2019 9:33PM | N | Jaodand |
20 | 300466 | 22845 | ACIS-S | HETG | 30.000000 | 29.948800 | V3890Sgr | archived | Aug 29 2019 3:41PM | Sep 3 2019 7:29AM | N | Orio |
20 | 300465 | 22682 | ACIS-S | NONE | 15.000000 | 15.082639 | V1369Cen | archived | Jul 29 2019 11:01AM | Sep 2 2019 3:00AM | D | Drake |
20 | 402123 | 22289 | ACIS-S | NONE | 30.000000 | 30.070602 | SwiftJ1728.9-3613 | archived | Jul 16 2019 11:35AM | Jul 28 2019 5:19AM | D | Miller |
20 | 402122 | 22285 | ACIS-S | NONE | 10.000000 | 9.558000 | 4U1901+03 | archived | Jul 9 2019 1:45PM | Jul 14 2019 7:41AM | N | Lutovinov |
20 | 402121 | 22277 | ACIS-S | HETG | 25.000000 | 26.652000 | 4U1820-30 | archived | Jul 3 2019 1:55PM | Jul 8 2019 1:09PM | N | Heinke |
20 | 402121 | 22276 | ACIS-S | HETG | 25.000000 | 26.909000 | 4U1820-30 | archived | Jul 3 2019 11:35AM | Jul 7 2019 5:22PM | N | Heinke |
20 | 503149 | 22271 | ACIS-S | NONE | 15.000000 | 15.091639 | SN2003gk | archived | Jun 17 2019 10:22AM | Aug 5 2019 3:47PM | N | Patnaude |
20 | 703897 | 22240 | ACIS-S | HETG | 10.000000 | 10.069509 | PKS1830-211 | archived | May 22 2019 1:06PM | Jun 16 2019 4:22PM | D | Buson |
20 | 703896 | 22239 | ACIS-S | HETG | 10.000000 | 10.070393 | PKS1830-211 | archived | May 22 2019 1:06PM | Jun 15 2019 10:43PM | D | Buson |
20 | 402117 | 22213 | ACIS-S | HETG | 30.000000 | 30.078001 | GRS1915+105 | archived | Apr 25 2019 11:45AM | Apr 30 2019 4:49AM | D | Miller |
20 | 703892 | 22212 | ACIS-S | NONE | 20.000000 | 20.082000 | SDSSJ085051.98+0830 | archived | Apr 22 2019 2:33PM | May 12 2019 6:37PM | N | Civano |
20 | 703887 | 22199 | ACIS-S | HETG | 25.000000 | 25.995974 | PKS1830-211 | archived | Apr 15 2019 12:45PM | May 24 2019 8:25PM | N | Buson |
20 | 703886 | 22198 | ACIS-S | HETG | 20.000000 | 20.069181 | PKS1830-211 | archived | Apr 15 2019 12:45PM | May 7 2019 12:51PM | N | Buson |
20 | 703885 | 22197 | ACIS-S | HETG | 15.000000 | 14.069199 | PKS1830-211 | archived | Apr 15 2019 12:45PM | Apr 19 2019 7:16AM | N | Buson |
20 | 201266 | 22186 | ACIS-S | HETG | 12.600000 | 12.647713 | ProximaCentauri | archived | Apr 8 2019 4:41PM | May 6 2019 4:05AM | D | MacGregor |
20 | 201265 | 22185 | ACIS-S | HETG | 12.600000 | 13.062752 | ProximaCentauri | archived | Apr 8 2019 4:41PM | May 3 2019 3:58AM | D | MacGregor |
20 | 703879 | 22183 | ACIS-S | NONE | 10.000000 | 10.108726 | NAMEAT2019ahk | archived | Apr 5 2019 11:22AM | Jun 9 2019 12:47AM | D | Alexander |
20 | 703878 | 22182 | ACIS-S | NONE | 10.000000 | 10.109100 | NAMEAT2019ahk | archived | Apr 5 2019 11:22AM | Apr 17 2019 12:57PM | D | Alexander |
20 | 100182 | 22159 | HRC-I | NONE | 36.000000 | 36.101783 | Jupiter | archived | Mar 12 2019 6:23PM | May 29 2019 3:43AM | N | Gladstone |
20 | 402115 | 22134 | HRC-I | NONE | 2.000000 | 2.182481 | 4U1901+03 | archived | Feb 14 2019 5:10PM | Mar 5 2019 5:57PM | N | Hemphill |
20 | 703863 | 22096 | ACIS-S | NONE | 80.000000 | 73.566101 | GSN069 | archived | Jan 31 2019 12:33PM | Feb 14 2019 4:52PM | D | Miniutti |
20 | 402114 | 22095 | ACIS-S | NONE | 15.000000 | 15.090000 | SXP4.78 | archived | Jan 30 2019 4:59PM | Mar 1 2019 1:20AM | N | Lutovinov |
19 | 703841 | 22021 | ACIS-S | NONE | 1.500000 | 1.426000 | [SDK2021]GraLJ1817 | archived | Nov 30 2018 11:42AM | May 30 2019 3:06AM | D | Pooley |
19 | 703840 | 22020 | ACIS-S | NONE | 1.500000 | 1.612000 | [LAM2018]J1721+8842 | archived | Nov 30 2018 11:42AM | May 30 2019 2:12AM | D | Pooley |
19 | 703839 | 22019 | ACIS-S | NONE | 1.500000 | 1.592900 | [SDK2021]GraLJ1537 | archived | Nov 30 2018 11:42AM | May 11 2019 7:53AM | D | Pooley |
19 | 703838 | 22018 | ACIS-S | NONE | 1.500000 | 1.692600 | [SDK2021]GraLJ0659 | archived | Nov 30 2018 11:42AM | Jan 15 2019 2:26PM | D | Pooley |
19 | 703837 | 22017 | ACIS-S | NONE | 1.500000 | 1.608900 | [SMC2017]WISEJ2344 | archived | Nov 30 2018 11:42AM | Apr 16 2019 3:38AM | D | Pooley |
19 | 703836 | 22016 | ACIS-S | NONE | 1.500000 | 1.610558 | SDSSJ1251+2935 | archived | Nov 30 2018 11:42AM | Mar 16 2019 6:21AM | D | Pooley |
19 | 703835 | 22015 | ACIS-S | NONE | 1.500000 | 1.608770 | DESJ0420-4037 | archived | Nov 30 2018 11:42AM | May 10 2019 9:35PM | D | Pooley |
19 | 703834 | 22014 | ACIS-S | NONE | 1.500000 | 1.612000 | DESJ040559.80-33085 | archived | Nov 30 2018 11:42AM | May 13 2019 12:46AM | D | Pooley |
19 | 703833 | 22013 | ACIS-S | NONE | 1.500000 | 1.608679 | DESJ0029-3814 | archived | Nov 30 2018 11:42AM | Jan 29 2019 10:08AM | D | Pooley |
19 | 201264 | 22012 | ACIS-S | NONE | 20.000000 | 19.064912 | HD60848 | archived | Nov 30 2018 11:26AM | Dec 30 2018 1:30AM | D | Rauw |
19 | 402113 | 21868 | ACIS-S | NONE | 20.000000 | 19.948800 | GS1354-64 | archived | Sep 26 2018 4:18PM | Oct 8 2018 6:22AM | D | Reynolds |
19 | 402112 | 21866 | ACIS-S | NONE | 3.000000 | 3.090700 | [OBM2019]ESO338-4 | archived | Sep 21 2018 3:35PM | Nov 19 2018 1:39AM | D | Oskinova |
19 | 201263 | 21855 | ACIS-S | NONE | 20.000000 | 20.171700 | 2MASSJ05351918-0518 | archived | Sep 7 2018 5:24PM | Dec 11 2018 11:29PM | N | Cleeves |
19 | 201262 | 21854 | ACIS-S | NONE | 20.000000 | 20.058950 | 2MASSJ05351918-0518 | archived | Sep 7 2018 5:24PM | Dec 5 2018 10:50AM | N | Cleeves |
19 | 703832 | 21732 | ACIS-S | NONE | 10.000000 | 10.062600 | TXS2116-077 | archived | Aug 20 2018 10:29AM | Sep 15 2018 8:42AM | D | Paliya |
19 | 300461 | 21671 | HRC-S | LETG | 10.000000 | 9.766457 | VWHyi | archived | Aug 5 2018 2:13PM | Aug 8 2018 12:29AM | N | Knigge |
19 | 503140 | 21660 | ACIS-S | NONE | 20.000000 | 20.088000 | SN2012au | archived | Jul 17 2018 3:50PM | Aug 2 2018 1:57PM | D | Patnaude |
19 | 503053 | 21122 | HRC-S | LETG | 50.000000 | 47.288378 | SN2018cow | archived | Jun 21 2018 1:05PM | Jun 24 2018 3:21PM | N | Maccarone |
19 | 201206 | 21102 | HRC-I | NONE | 30.000000 | 30.146533 | ALPHABOO | archived | May 24 2018 9:20AM | Jun 10 2018 7:57PM | S | AYRES |
19 | 703679 | 21097 | ACIS-S | NONE | 10.000000 | 10.080000 | SDSSJ110731.23+1347 | archived | May 9 2018 8:55AM | Jun 14 2018 3:47AM | N | Chilingarian |
19 | 703678 | 21091 | ACIS-S | NONE | 10.000000 | 10.074876 | NGC3893 | archived | Apr 19 2018 3:33PM | Jun 28 2018 11:41AM | N | McHardy |
19 | 402025 | 21090 | ACIS-S | NONE | 47.000000 | 46.610473 | GW170817 | archived | Apr 18 2018 3:51PM | May 5 2018 1:25AM | N | Wilkes |
19 | 402026 | 21083 | ACIS-S | HETG | 30.000000 | 30.079042 | SwiftJ1658.2-4242 | archived | Apr 16 2018 1:48PM | Apr 28 2018 1:26AM | D | Ponti |
19 | 503043 | 21082 | ACIS-S | NONE | 23.000000 | 23.091000 | SN2011ja | archived | Apr 11 2018 3:00PM | Dec 6 2018 1:03AM | S | Patnaude |
19 | 402025 | 21080 | ACIS-S | NONE | 53.000000 | 51.456900 | GW170817 | archived | Apr 11 2018 9:41AM | May 3 2018 10:41AM | N | Wilkes |
19 | 703677 | 21076 | ACIS-S | NONE | 10.000000 | 9.972748 | M87 | archived | Apr 2 2018 9:13PM | Apr 24 2018 1:48PM | N | Wong |
19 | 703676 | 21075 | ACIS-S | NONE | 10.000000 | 10.069495 | M87 | archived | Apr 2 2018 9:13PM | Apr 22 2018 12:19AM | N | Wong |
19 | 703675 | 21058 | HRC-I | NONE | 15.000000 | 14.779732 | 3C264 | archived | Mar 20 2018 11:20AM | Apr 4 2018 7:08PM | N | Santander |
19 | 503052 | 21040 | ACIS-S | NONE | 20.000000 | 20.050800 | iPTF14hls | archived | Mar 6 2018 7:18AM | Apr 4 2018 1:10PM | D | MARGUTTI |
19 | 703674 | 21033 | ACIS-S | NONE | 11.300000 | 11.352200 | UGC416 | archived | Feb 26 2018 12:39PM | Sep 9 2018 3:35PM | S | Gallo |
19 | 703673 | 21032 | ACIS-S | NONE | 9.600000 | 9.653400 | LSBCF570-05 | archived | Feb 26 2018 12:39PM | Jun 28 2018 8:36AM | S | Gallo |
19 | 703672 | 21031 | ACIS-S | NONE | 8.400000 | 8.474345 | UGC11578 | archived | Feb 26 2018 12:39PM | Aug 5 2018 12:06PM | S | Gallo |
19 | 703671 | 21030 | ACIS-S | NONE | 7.800000 | 7.852300 | UGC10015 | archived | Feb 26 2018 12:39PM | May 7 2018 9:09PM | S | Gallo |
19 | 703670 | 21029 | ACIS-S | NONE | 7.700000 | 7.963900 | UGC10017 | archived | Feb 26 2018 12:39PM | May 17 2018 3:52AM | S | Gallo |
19 | 703669 | 21028 | ACIS-S | NONE | 7.400000 | 7.650720 | UGC09927 | archived | Feb 26 2018 12:39PM | May 6 2018 2:56PM | S | Gallo |
19 | 703668 | 21027 | ACIS-S | NONE | 6.900000 | 6.792100 | UGC05750 | archived | Feb 26 2018 12:39PM | Mar 21 2018 12:17PM | S | Gallo |
19 | 703667 | 21026 | ACIS-S | NONE | 6.700000 | 6.754900 | UGC04669 | archived | Feb 26 2018 12:39PM | May 23 2018 9:51PM | S | Gallo |
19 | 703666 | 21025 | ACIS-S | NONE | 5.800000 | 5.691445 | UGC1230 | archived | Feb 26 2018 12:39PM | Nov 14 2018 5:50AM | S | Gallo |
19 | 703665 | 21024 | ACIS-S | NONE | 5.800000 | 5.852800 | UGC05005 | archived | Feb 26 2018 12:39PM | Jun 19 2018 4:26PM | S | Gallo |
19 | 703664 | 21023 | ACIS-S | NONE | 15.600000 | 15.070960 | LSBCF583-04 | archived | Feb 26 2018 12:39PM | May 24 2018 9:33PM | S | Gallo |
19 | 703663 | 21022 | ACIS-S | NONE | 12.600000 | 12.654111 | LSBCF576-01 | archived | Feb 26 2018 12:39PM | Aug 13 2018 11:20AM | S | Gallo |
19 | 703662 | 21021 | ACIS-S | NONE | 10.400000 | 10.450100 | LSBCF743-01 | archived | Feb 26 2018 12:39PM | Sep 2 2018 7:07AM | S | Gallo |
19 | 703661 | 21020 | ACIS-S | NONE | 7.100000 | 7.154491 | LSBCF612-01 | archived | Feb 26 2018 12:39PM | Sep 24 2018 8:47PM | S | Gallo |
19 | 703660 | 21019 | ACIS-S | NONE | 6.500000 | 6.553400 | LSBCF544-01 | archived | Feb 26 2018 12:39PM | Nov 14 2018 3:44AM | S | Gallo |
19 | 703659 | 21018 | ACIS-S | NONE | 6.400000 | 6.451100 | UGC09024 | archived | Feb 26 2018 12:39PM | Apr 4 2018 3:50AM | S | Gallo |
19 | 703658 | 21017 | ACIS-S | NONE | 9.000000 | 9.048900 | LSBCF750-04 | archived | Feb 26 2018 12:39PM | Aug 26 2018 11:56PM | S | Gallo |
19 | 703657 | 21016 | ACIS-S | NONE | 7.400000 | 7.449300 | IC3605 | archived | Feb 26 2018 12:39PM | Apr 3 2018 2:35PM | S | Gallo |
19 | 703656 | 21015 | ACIS-S | NONE | 7.100000 | 6.990500 | UGC06151 | archived | Feb 26 2018 12:39PM | Mar 21 2018 10:03AM | S | Gallo |
19 | 703655 | 21014 | ACIS-S | NONE | 6.700000 | 6.742500 | LSBCF570-06 | archived | Feb 26 2018 12:39PM | Nov 25 2018 11:32AM | S | Gallo |
19 | 703654 | 21013 | ACIS-S | NONE | 6.100000 | 6.150214 | UGC05629 | archived | Feb 26 2018 12:39PM | Jul 2 2018 8:59PM | S | Gallo |
19 | 703653 | 21012 | ACIS-S | NONE | 5.900000 | 5.952000 | LSBCF574-09 | archived | Feb 26 2018 12:39PM | Apr 14 2018 10:37AM | S | Gallo |
19 | 703652 | 21011 | ACIS-S | NONE | 4.800000 | 4.854437 | UGC05675 | archived | Feb 26 2018 12:39PM | Mar 21 2018 8:26AM | S | Gallo |
19 | 703651 | 21010 | ACIS-S | NONE | 3.600000 | 3.492606 | UGC08839 | archived | Feb 26 2018 12:39PM | Apr 3 2018 5:04PM | S | Gallo |
19 | 703650 | 21009 | ACIS-S | NONE | 3.600000 | 3.651473 | LSBCF574-07 | archived | Feb 26 2018 12:39PM | May 10 2018 2:20PM | S | Gallo |
19 | 703649 | 21008 | ACIS-S | NONE | 3.200000 | 3.297175 | LSBCF574-08 | archived | Feb 26 2018 12:39PM | Jun 25 2018 9:22PM | S | Gallo |
19 | 703648 | 21007 | ACIS-S | NONE | 3.200000 | 3.253765 | CGCG098-132 | archived | Feb 26 2018 12:39PM | Jun 8 2018 11:49AM | S | Gallo |
19 | 703647 | 21006 | ACIS-S | NONE | 3.200000 | 3.329400 | LSBCF570-04 | archived | Feb 26 2018 12:39PM | Jun 10 2018 12:24AM | S | Gallo |
19 | 503051 | 21005 | ACIS-S | NONE | 22.000000 | 21.963000 | SN2013df | archived | Feb 26 2018 12:38PM | Mar 26 2018 8:10PM | S | Patnaude |
19 | 503050 | 21004 | ACIS-S | NONE | 15.000000 | 15.090000 | SN2003gk | archived | Feb 26 2018 12:38PM | Aug 21 2018 2:14AM | S | Patnaude |
19 | 503049 | 21003 | ACIS-S | NONE | 22.000000 | 22.092000 | SN2013ak | archived | Feb 26 2018 12:38PM | Aug 5 2018 8:04PM | S | Patnaude |
19 | 503048 | 21002 | ACIS-S | NONE | 10.000000 | 10.092000 | SN2013by | archived | Feb 26 2018 12:38PM | Jun 19 2018 5:42AM | S | Patnaude |
19 | 503047 | 21001 | ACIS-S | NONE | 10.000000 | 10.091451 | SN2012aw | archived | Feb 26 2018 12:38PM | Mar 26 2018 4:54PM | S | Patnaude |
19 | 503046 | 21000 | ACIS-S | NONE | 10.000000 | 10.091748 | SN2013ej | archived | Feb 26 2018 12:38PM | Sep 30 2018 8:35PM | S | Patnaude |
19 | 503045 | 20999 | ACIS-S | NONE | 15.000000 | 15.089764 | SN2008ax | archived | Feb 26 2018 12:38PM | Nov 6 2018 2:46AM | S | Patnaude |
19 | 503044 | 20998 | ACIS-S | NONE | 20.000000 | 20.091000 | SN2011dh | archived | Feb 26 2018 12:38PM | Aug 31 2018 4:28PM | S | Patnaude |
19 | 503043 | 20997 | ACIS-S | NONE | 19.000000 | 20.990564 | SN2011ja | archived | Feb 26 2018 12:38PM | Apr 24 2018 9:33PM | S | Patnaude |
19 | 201206 | 20996 | HRC-I | NONE | 50.000000 | 50.055878 | ALPHABOO | archived | Feb 26 2018 12:37PM | Jun 9 2018 10:06AM | S | AYRES |
19 | 402024 | 20995 | ACIS-S | NONE | 17.000000 | 16.244000 | NGC5907 | archived | Feb 22 2018 9:22AM | Mar 1 2018 4:42AM | D | Pintore |
19 | 402024 | 20994 | ACIS-S | NONE | 33.000000 | 33.049100 | NGC5907 | archived | Feb 21 2018 10:51PM | Feb 27 2018 1:40PM | D | Pintore |
19 | 201205 | 20987 | HRC-I | NONE | 5.000000 | 5.180350 | ALPHACENTAURI | archived | Feb 16 2018 9:52AM | May 18 2018 5:25PM | N | AYRES |
19 | 402022 | 20966 | ACIS-S | NONE | 10.000000 | 10.069904 | NGC300ULX-1 | archived | Jan 26 2018 10:21PM | Feb 11 2018 4:49PM | D | Vasilopoulos |
19 | 402021 | 20965 | ACIS-S | NONE | 10.000000 | 10.070236 | NGC300ULX-1 | archived | Jan 26 2018 10:21PM | Feb 8 2018 3:10AM | D | Vasilopoulos |
19 | 402020 | 20945 | ACIS-S | NONE | 13.000000 | 14.405700 | GW170817 | archived | Jan 18 2018 4:25PM | Jan 28 2018 4:29AM | N | Wilkes |
19 | 402020 | 20939 | ACIS-S | NONE | 19.700000 | 22.541809 | GW170817 | archived | Jan 7 2018 10:35PM | Jan 24 2018 8:18AM | N | Wilkes |
19 | 402020 | 20938 | ACIS-S | NONE | 16.000000 | 16.067231 | GW170817 | archived | Jan 7 2018 10:35PM | Jan 21 2018 1:45PM | N | Wilkes |
19 | 402020 | 20937 | ACIS-S | NONE | 19.100000 | 21.045162 | GW170817 | archived | Jan 7 2018 10:34PM | Jan 23 2018 8:02AM | N | Wilkes |
19 | 402020 | 20936 | ACIS-S | NONE | 32.200000 | 32.168700 | GW170817 | archived | Jan 5 2018 2:26PM | Jan 17 2018 9:55PM | N | Wilkes |
18 | 402019 | 20928 | ACIS-S | NONE | 10.000000 | 10.068146 | LSV+2225 | archived | Dec 22 2017 1:17PM | Jan 13 2018 3:23PM | D | Liu |
18 | 703470 | 20887 | ACIS-S | NONE | 22.500000 | 20.654316 | QSOJ1342+0928 | archived | Dec 1 2017 12:31PM | Dec 17 2017 7:01AM | D | Banados |
18 | 201204 | 20875 | ACIS-S | NONE | 4.000000 | 4.091577 | DMTau | archived | Nov 22 2017 11:54AM | Jan 25 2018 8:15AM | N | Cleeves |
18 | 201203 | 20874 | ACIS-S | NONE | 4.000000 | 4.092000 | DMTau | archived | Nov 22 2017 11:54AM | Jan 17 2018 7:57PM | N | Cleeves |
18 | 201202 | 20873 | ACIS-S | NONE | 4.000000 | 4.092000 | DMTau | archived | Nov 22 2017 11:54AM | Jan 9 2018 10:33PM | N | Cleeves |
18 | 201201 | 20872 | ACIS-S | NONE | 4.000000 | 4.092000 | DMTau | archived | Nov 22 2017 11:54AM | Jan 4 2018 11:59AM | N | Cleeves |
18 | 201200 | 20871 | ACIS-S | NONE | 4.000000 | 4.090868 | DMTau | archived | Nov 22 2017 11:54AM | Dec 27 2017 3:11PM | N | Cleeves |
18 | 201199 | 20870 | ACIS-S | NONE | 4.000000 | 4.092000 | DMTau | archived | Nov 22 2017 11:54AM | Dec 21 2017 6:48AM | N | Cleeves |
18 | 201198 | 20869 | ACIS-S | NONE | 4.000000 | 4.092000 | DMTau | archived | Nov 22 2017 11:54AM | Dec 14 2017 12:03AM | N | Cleeves |
18 | 402012 | 20861 | ACIS-S | NONE | 25.000000 | 25.068738 | GW170817 | archived | Nov 16 2017 11:52AM | Dec 6 2017 11:02AM | N | Wilkes |
18 | 402012 | 20860 | ACIS-S | NONE | 75.000000 | 75.066017 | GW170817 | archived | Nov 16 2017 11:48AM | Dec 3 2017 1:59AM | N | Wilkes |
18 | 402011 | 20859 | ACIS-S | HETG | 25.000000 | 25.090000 | SwiftJ0243.6+6124 | archived | Nov 8 2017 1:06PM | Nov 11 2017 11:20AM | D | Degenaar |
18 | 801803 | 20851 | ACIS-I | NONE | 34.000000 | 31.734444 | 1RXSJ032401.8+24213 | archived | Nov 6 2017 4:45PM | Jan 2 2018 1:17AM | N | Ebeling |
18 | 100171 | 20847 | HRC-I | NONE | 25.000000 | 25.050233 | Uranus | archived | Oct 29 2017 1:57PM | Nov 12 2017 1:14PM | D | Dunn |
18 | 100171 | 20846 | HRC-I | NONE | 25.000000 | 25.144533 | Uranus | archived | Oct 29 2017 12:00PM | Nov 11 2017 7:47PM | D | Dunn |
18 | 201197 | 20831 | ACIS-S | NONE | 10.000000 | 10.065700 | AT2017gbl | archived | Oct 17 2017 3:45PM | Nov 3 2017 12:18PM | N | Heikkila |
18 | 402010 | 20830 | ACIS-S | NONE | 50.000000 | 51.946700 | NGC5907ULX | archived | Oct 17 2017 12:11PM | Nov 7 2017 6:11AM | D | belfiore |
18 | 503034 | 20728 | ACIS-S | NONE | 50.000000 | 47.309100 | GRB170817A | archived | Aug 29 2017 12:49PM | Sep 1 2017 3:43PM | D | Troja |
18 | 300403 | 20632 | HRC-S | LETG | 35.000000 | 34.406433 | NovaLup2016 | archived | Aug 11 2017 3:25PM | Aug 30 2017 3:37PM | N | Orio |
18 | 703616 | 20625 | ACIS-S | NONE | 10.000000 | 10.061465 | AT2017eqx | archived | Jul 31 2017 3:41PM | Aug 16 2017 10:53AM | D | Nicholl |
18 | 503033 | 20613 | ACIS-S | NONE | 15.000000 | 15.059262 | GRB170714A | archived | Jul 24 2017 4:32PM | Jul 28 2017 11:57AM | N | Troja |
18 | 703470 | 20124 | ACIS-S | NONE | 27.500000 | 25.059603 | QSOJ1342+0928 | archived | Jul 12 2017 4:47PM | Dec 15 2017 1:55PM | D | Banados |
18 | 703469 | 20115 | ACIS-S | NONE | 10.000000 | 10.089000 | SDSSJ135750.71+22310 | archived | Jun 29 2017 7:05PM | Aug 27 2017 7:51AM | N | Chilingarian |
18 | 703468 | 20114 | ACIS-S | NONE | 10.000000 | 10.092000 | SDSSJ110731.23+13471 | archived | Jun 29 2017 7:05PM | Jul 17 2017 12:21AM | N | Chilingarian |
18 | 401894 | 20098 | HRC-S | NONE | 30.000000 | 30.092977 | MAXIJ0911-655 | archived | Jun 1 2017 12:26PM | Jun 25 2017 7:07AM | D | Riggio |
18 | 401893 | 20083 | ACIS-S | NONE | 8.000000 | 7.678800 | SWIFTJ175233.9-2909 | archived | May 15 2017 4:03PM | May 25 2017 3:36AM | N | Maccarone |
18 | 502973 | 20055 | ACIS-S | NONE | 50.000000 | 51.010332 | SN2017cbv | archived | Mar 23 2017 2:47PM | Mar 27 2017 11:54AM | D | Drout |
18 | 401892 | 20054 | ACIS-I | NONE | 65.000000 | 65.099750 | PSRB1259-63 | archived | Mar 17 2017 11:23AM | Apr 24 2017 5:27AM | N | Pavlov |
18 | 703466 | 20035 | ACIS-S | NONE | 14.400000 | 14.469199 | M87 | archived | Feb 27 2017 7:29PM | Apr 14 2017 2:13AM | N | Neilsen |
18 | 703466 | 20034 | ACIS-S | NONE | 14.400000 | 14.467599 | M87 | archived | Feb 27 2017 3:14PM | Apr 12 2017 12:00AM | N | Neilsen |
18 | 703465 | 20021 | ACIS-S | NONE | 10.000000 | 10.049712 | WPVS007 | archived | Feb 16 2017 5:44PM | Mar 16 2017 3:24PM | N | Grupe |
18 | 401891 | 20008 | ACIS-S | HETG | 30.000000 | 30.071250 | GRS1716-249 | archived | Jan 31 2017 1:22PM | Feb 6 2017 12:24PM | D | Miller |
18 | 100168 | 20002 | HRC-I | NONE | 36.000000 | 36.164821 | Jupiter | archived | Jan 26 2017 2:50PM | Aug 6 2017 2:08AM | N | Jackman |
18 | 100167 | 20001 | HRC-I | NONE | 36.000000 | 37.147283 | Jupiter | archived | Jan 26 2017 2:50PM | Jun 18 2017 6:57PM | N | Jackman |
18 | 100166 | 20000 | HRC-I | NONE | 72.000000 | 72.138735 | Jupiter | archived | Jan 26 2017 2:50PM | Feb 28 2017 12:53PM | N | Jackman |
18 | 502972 | 19999 | ACIS-S | NONE | 10.000000 | 9.978900 | iPTF17cw | archived | Jan 23 2017 5:25PM | Feb 8 2017 9:39AM | D | Corsi |
17 | 703464 | 19990 | ACIS-S | NONE | 30.000000 | 30.090000 | SDSSJ140737.16+4428 | archived | Jan 11 2017 10:36AM | Feb 25 2017 2:51PM | D | Secrest |
17 | 502971 | 19986 | ACIS-S | NONE | 30.000000 | 29.771358 | CRTSCSS161010J0458 | archived | Dec 21 2016 4:13PM | Jul 23 2017 9:17PM | D | MARGUTTI |
17 | 502970 | 19985 | ACIS-S | NONE | 30.000000 | 27.416074 | CRTSCSS161010J0458 | archived | Dec 21 2016 4:13PM | Feb 13 2017 12:16PM | D | MARGUTTI |
17 | 502969 | 19984 | ACIS-S | NONE | 30.000000 | 30.045200 | CRTSCSS161010J0458 | archived | Dec 21 2016 4:13PM | Jan 13 2017 11:32PM | D | MARGUTTI |
17 | 300401 | 19983 | HRC-S | LETG | 50.000000 | 50.185284 | ASASSN-16oh | archived | Dec 19 2016 2:25PM | Dec 28 2016 9:27PM | D | Maccarone |
17 | 401890 | 19904 | ACIS-S | HETG | 30.000000 | 31.052750 | 4U1630-47 | archived | Oct 6 2016 2:17PM | Oct 21 2016 1:43AM | D | Bhattacharyya |
17 | 401889 | 19891 | ACIS-S | NONE | 35.000000 | 36.302609 | CXOUJ103844.8+53300 | archived | Sep 22 2016 2:40PM | Oct 22 2016 4:32PM | N | Earnshaw |
17 | 201154 | 19793 | HRC-I | NONE | 11.250000 | 10.889601 | ProximaCen | archived | Sep 6 2016 5:03PM | Dec 8 2016 8:29PM | N | Wargelin |
17 | 201153 | 19790 | HRC-I | NONE | 11.250000 | 10.889729 | ProximaCen | archived | Sep 1 2016 4:40PM | Nov 3 2016 6:43PM | N | Wargelin |
17 | 201152 | 19789 | HRC-I | NONE | 11.250000 | 10.922401 | ProximaCen | archived | Sep 1 2016 4:40PM | Oct 14 2016 6:31PM | N | Wargelin |
17 | 201151 | 19788 | HRC-I | NONE | 11.250000 | 12.464001 | ProximaCen | archived | Sep 1 2016 4:40PM | Sep 26 2016 8:12AM | N | Wargelin |
17 | 401888 | 19787 | ACIS-S | HETG | 15.000000 | 15.040450 | SMCX-3 | archived | Aug 30 2016 11:23AM | Sep 7 2016 4:45PM | D | Coe |
17 | 401888 | 19786 | ACIS-S | HETG | 25.000000 | 24.042227 | SMCX-3 | archived | Aug 30 2016 11:18AM | Sep 6 2016 7:50PM | D | Coe |
17 | 401881 | 19691 | ACIS-I | NONE | 1.000000 | 1.081900 | PMNJ0032-7306 | archived | Aug 3 2016 2:10PM | Aug 11 2016 11:00PM | D | Kennea |
17 | 502963 | 19690 | ACIS-S | NONE | 60.000000 | 56.230900 | PSRJ1119-6127 | archived | Aug 2 2016 6:22PM | Oct 27 2016 6:38PM | N | Blumer |
17 | 300392 | 18889 | ACIS-S | NONE | 18.000000 | 18.027750 | FOAqr | archived | Jul 14 2016 11:46AM | Jul 26 2016 7:26AM | N | Kennedy |
17 | 401819 | 18885 | ACIS-S | NONE | 25.000000 | 25.535198 | XMMUJ004855.5-73494 | archived | Jun 30 2016 11:04AM | Jul 6 2016 8:43AM | N | Vasilopoulos |
17 | 502667 | 18884 | ACIS-S | NONE | 20.000000 | 20.069599 | SGR1935+2154 | archived | Jun 29 2016 3:51PM | Jul 7 2016 5:43AM | D | Kouveliotou |
17 | 502666 | 18880 | ACIS-S | NONE | 30.000000 | 29.047000 | Gaia16apd | archived | Jun 27 2016 12:27PM | Mar 19 2017 5:29PM | D | Yan |
17 | 502665 | 18879 | ACIS-S | NONE | 30.000000 | 30.032422 | Gaia16apd | archived | Jun 27 2016 12:27PM | Oct 23 2016 6:11PM | D | Yan |
17 | 502664 | 18878 | ACIS-S | NONE | 47.000000 | 44.185500 | PKS1613-50 | archived | Jun 23 2016 2:38PM | Jun 25 2016 9:30AM | D | Rea |
17 | 502663 | 18827 | ACIS-S | NONE | 15.000000 | 15.081000 | SN2016bkv | archived | Apr 1 2016 1:03PM | Apr 20 2016 4:10AM | N | Patnaude |
17 | 401818 | 18815 | ACIS-S | NONE | 30.000000 | 30.090000 | HETEJ1900.1-2455 | archived | Mar 17 2016 5:15PM | Apr 18 2016 10:09PM | D | Degenaar |
17 | 703301 | 18813 | ACIS-S | NONE | 5.000000 | 5.068768 | M87 | archived | Mar 9 2016 8:02PM | Mar 17 2016 3:43AM | N | Cheung |
17 | 703300 | 18812 | ACIS-S | NONE | 5.000000 | 4.853443 | M87 | archived | Mar 9 2016 8:02PM | Mar 16 2016 12:27AM | N | Cheung |
17 | 703299 | 18811 | ACIS-S | NONE | 5.000000 | 5.069200 | M87 | archived | Mar 9 2016 8:02PM | Mar 14 2016 1:44PM | N | Cheung |
17 | 703298 | 18810 | ACIS-S | NONE | 5.000000 | 5.069600 | M87 | archived | Mar 9 2016 8:02PM | Mar 13 2016 7:25AM | N | Cheung |
17 | 703297 | 18809 | ACIS-S | NONE | 5.000000 | 4.984400 | M87 | archived | Mar 9 2016 8:02PM | Mar 12 2016 5:07AM | N | Cheung |
17 | 703296 | 18804 | ACIS-S | NONE | 30.000000 | 30.062316 | QSO2237+0305 | archived | Mar 9 2016 1:39PM | Apr 24 2016 5:27AM | N | Pooley |
17 | 502662 | 18802 | ACIS-S | NONE | 36.000000 | 36.062177 | SN2005ip | archived | Mar 2 2016 12:16PM | Apr 4 2016 2:16AM | N | Mauerhan |
17 | 300391 | 18800 | ACIS-S | NONE | 25.000000 | 25.103556 | MWC560 | archived | Feb 25 2016 5:26PM | Mar 9 2016 2:20AM | D | Lucy |
17 | 300391 | 18790 | ACIS-S | NONE | 25.000000 | 25.101000 | MWC560 | archived | Feb 23 2016 2:41PM | Mar 8 2016 7:17AM | D | Lucy |
17 | 703295 | 18789 | ACIS-S | NONE | 30.000000 | 29.978798 | Mrk1018 | archived | Feb 18 2016 12:45PM | Feb 25 2016 2:37AM | D | Tremblay |
17 | 401817 | 18788 | ACIS-S | NONE | 5.000000 | 4.956140 | PSRJ2032+4127 | archived | Feb 15 2016 5:13PM | Feb 24 2016 8:23AM | N | Ho |
17 | 502661 | 18760 | ACIS-S | NONE | 5.000000 | 5.025100 | ASASSN16at | archived | Jan 26 2016 11:14AM | Feb 6 2016 6:57AM | N | Grupe |
16 | 201084 | 18725 | ACIS-S | NONE | 20.000000 | 20.094000 | HD97658 | archived | Dec 3 2015 10:31AM | Mar 5 2016 4:21PM | D | Wheatley |
16 | 201084 | 18724 | ACIS-S | NONE | 20.000000 | 20.094000 | HD97658 | archived | Dec 3 2015 9:52AM | Dec 11 2015 1:01PM | D | Wheatley |
16 | 502660 | 18717 | ACIS-S | NONE | 40.000000 | 40.092000 | FRB121102 | archived | Nov 19 2015 11:14AM | Nov 23 2015 10:37AM | D | Scholz |
16 | 401816 | 18686 | HRC-S | NONE | 2.800000 | 2.938931 | SMCX-2 | archived | Oct 1 2015 5:25PM | Nov 5 2015 6:56PM | N | Li |
16 | 703280 | 18352 | ACIS-S | NONE | 10.000000 | 10.124600 | NGC660 | archived | Jul 22 2015 3:32PM | Aug 26 2015 8:37PM | N | Annuar |
16 | 100155 | 17709 | ACIS-S | NONE | 110.000000 | 107.221501 | Pluto(134340) | archived | Jul 15 2015 3:19PM | Aug 1 2015 9:30PM | N | McNutt |
16 | 100155 | 17708 | ACIS-S | NONE | 16.000000 | 17.595600 | Pluto(134340) | archived | Jul 15 2015 3:19PM | Jul 30 2015 5:30AM | N | McNutt |
16 | 401698 | 17704 | ACIS-S | NONE | 28.000000 | 28.752000 | V404Cyg | archived | Jul 14 2015 3:56PM | Jul 25 2015 6:46PM | N | Heinz |
16 | 100155 | 17703 | ACIS-S | NONE | 14.000000 | 14.088741 | Pluto(134340) | archived | Jul 9 2015 1:59PM | Jul 27 2015 12:09AM | N | McNutt |
16 | 401697 | 17701 | ACIS-S | HETG | 40.000000 | 40.035879 | V404Cyg | archived | Jul 2 2015 3:23PM | Jul 11 2015 1:17PM | N | Neilsen |
16 | 401696 | 17697 | ACIS-S | HETG | 25.000000 | 24.712915 | v404Cyg | archived | Jun 22 2015 7:37PM | Jun 23 2015 9:40PM | N | King |
16 | 401695 | 17696 | ACIS-S | HETG | 30.000000 | 29.307864 | v404Cyg | archived | Jun 19 2015 9:29AM | Jun 22 2015 1:56PM | N | King |
16 | 401694 | 17678 | ACIS-I | NONE | 10.000000 | 10.102500 | M82 | archived | Jun 5 2015 2:09PM | Jun 21 2015 3:12AM | N | Brightman |
16 | 502493 | 17673 | ACIS-S | NONE | 10.000000 | 10.061636 | SNhunt275 | archived | May 26 2015 3:17PM | Sep 20 2015 11:42PM | N | MARGUTTI |
16 | 502492 | 17672 | ACIS-S | NONE | 10.000000 | 10.046760 | SNhunt275 | archived | May 26 2015 3:17PM | Jun 8 2015 2:04AM | N | MARGUTTI |
16 | 401693 | 17662 | ACIS-I | NONE | 5.000000 | 5.080900 | 2S1553-542 | archived | May 13 2015 4:36PM | May 21 2015 4:53PM | D | Lutovinov |
16 | 401692 | 17661 | HRC-S | NONE | 30.000000 | 29.765233 | SAXJ1808.4-3658 | archived | May 11 2015 2:47PM | May 24 2015 10:29PM | D | Patruno |
16 | 502491 | 17658 | ACIS-S | NONE | 25.000000 | 23.643700 | GRB150423A | archived | Apr 28 2015 3:13PM | May 2 2015 7:39AM | N | Berger |
16 | 401691 | 17649 | ACIS-S | HETG | 30.000000 | 30.073000 | 1RXSJ180408.9-34205 | archived | Apr 7 2015 1:46PM | Apr 14 2015 3:08PM | D | Degenaar |
16 | 300338 | 17648 | ACIS-S | HETG | 35.000000 | 34.947201 | GKPersei | archived | Mar 29 2015 7:31AM | Apr 4 2015 8:21AM | N | Orio |
16 | 201026 | 17644 | ACIS-S | NONE | 40.000000 | 38.690798 | RWAur | archived | Mar 20 2015 3:47PM | Apr 16 2015 6:56AM | N | Schneider |
16 | 502490 | 17639 | ACIS-S | NONE | 50.000000 | 47.108715 | CasACCO | archived | Mar 9 2015 4:35PM | May 1 2015 2:18AM | N | Posselt |
16 | 401690 | 17637 | ACIS-S | NONE | 10.000000 | 10.075000 | [PFH2005]622 | archived | Mar 4 2015 2:19PM | Mar 6 2015 4:48PM | N | Burrows |
16 | 703155 | 17636 | ACIS-S | NONE | 10.000000 | 10.056400 | WPVS007 | archived | Mar 4 2015 9:08AM | Mar 28 2015 8:20AM | N | Grupe |
16 | 401689 | 17631 | HRC-I | NONE | 10.000000 | 10.153651 | FRB150215 | archived | Feb 15 2015 11:51PM | Feb 18 2015 4:11AM | D | Petroff |
16 | 401688 | 17630 | ACIS-S | HETG | 15.000000 | 14.457600 | 4U1700-37 | archived | Feb 12 2015 5:51PM | Feb 22 2015 3:30AM | N | Oskinova |
16 | 703154 | 17594 | ACIS-S | NONE | 15.000000 | 15.058837 | SWIFTJ123205.1-1056 | archived | Jan 14 2015 5:56PM | Feb 10 2015 5:35AM | N | Levan |
16 | 502489 | 17586 | ACIS-S | NONE | 15.000000 | 15.066000 | SwiftJ123205.1-1056 | archived | Jan 6 2015 2:57PM | Jan 9 2015 11:55AM | N | Troja |
15 | 502488 | 17571 | ACIS-S | NONE | 10.000000 | 10.056279 | SN2014C | archived | Dec 15 2014 12:02PM | Aug 28 2015 9:03AM | N | MARGUTTI |
15 | 502487 | 17570 | ACIS-S | NONE | 10.000000 | 10.024851 | SN2014C | archived | Dec 15 2014 12:02PM | Apr 20 2015 10:47PM | N | MARGUTTI |
15 | 502486 | 17569 | ACIS-S | NONE | 10.000000 | 10.045655 | SN2014C | archived | Dec 15 2014 12:02PM | Jan 30 2015 3:22PM | N | MARGUTTI |
15 | 703152 | 17567 | HRC-S | LETG | 45.000000 | 44.793784 | ASASSN-14li | archived | Dec 4 2014 5:21PM | Dec 11 2014 9:09AM | N | Miller |
15 | 703152 | 17566 | HRC-S | LETG | 35.000000 | 35.039883 | ASASSN-14li | archived | Dec 4 2014 4:24PM | Dec 8 2014 11:29PM | N | Miller |
15 | 401686 | 17559 | ACIS-S | NONE | 40.000000 | 40.114000 | CXOJ122518.6+144545 | archived | Nov 26 2014 11:33AM | Dec 15 2014 6:27AM | D | Heida |
15 | 401685 | 17558 | ACIS-S | NONE | 20.000000 | 19.985700 | CXOJ122518.6+144545 | archived | Nov 26 2014 11:33AM | Dec 8 2014 5:42PM | D | Heida |
15 | 502485 | 17550 | ACIS-S | NONE | 20.000000 | 20.058751 | PSNJ12215757+042818 | archived | Nov 4 2014 4:44PM | Nov 16 2014 3:28PM | N | MARGUTTI |
15 | 703151 | 17547 | ACIS-S | NONE | 5.000000 | 5.071600 | NGC247 | archived | Oct 22 2014 11:11AM | Nov 12 2014 5:54AM | D | Feng |
15 | 703150 | 17538 | ACIS-S | NONE | 20.000000 | 20.078069 | SDSSJ152304.97+1145 | archived | Sep 26 2014 9:55AM | Dec 26 2014 4:59AM | D | Gallo |
15 | 502479 | 17314 | ACIS-S | NONE | 30.000000 | 29.154750 | SGR1935+2154 | archived | Aug 7 2014 3:43PM | Aug 31 2014 12:59AM | D | Rea |
15 | 200968 | 16631 | ACIS-S | NONE | 25.000000 | 23.011038 | V1180Cas | archived | Jun 20 2014 3:48PM | Aug 2 2014 10:11PM | N | Nucita |
15 | 401615 | 16625 | ACIS-S | NONE | 5.000000 | 5.147250 | PSRB1259-63 | archived | Jun 16 2014 12:48PM | Jun 25 2014 7:03PM | N | Bordas |
15 | 401614 | 16624 | ACIS-S | NONE | 5.000000 | 5.174750 | PSRB1259-63 | archived | Jun 16 2014 12:48PM | Jun 23 2014 6:46PM | N | Bordas |
15 | 502271 | 16618 | ACIS-S | NONE | 20.000000 | 20.063200 | GRB140515A | archived | May 20 2014 1:07PM | May 25 2014 7:54AM | N | MARGUTTI |
15 | 401613 | 16606 | ACIS-S | HETG | 35.000000 | 35.082250 | GROJ1744-28 | archived | Mar 22 2014 7:58PM | Mar 31 2014 12:48AM | D | Miller |
15 | 401613 | 16605 | ACIS-S | HETG | 35.000000 | 35.073250 | GROJ1744-28 | archived | Mar 22 2014 6:28PM | Mar 29 2014 7:09PM | D | Miller |
15 | 401612 | 16596 | ACIS-S | HETG | 10.000000 | 10.077500 | GROJ1744-28 | archived | Feb 17 2014 5:12PM | Mar 3 2014 9:15AM | D | Kennea |
14 | 401611 | 16583 | ACIS-I | NONE | 30.000000 | 28.538149 | PSRB1259-63 | archived | Jan 23 2014 6:17PM | Feb 9 2014 7:49AM | N | Pavlov |
15 | 502269 | 16580 | ACIS-S | NONE | 50.000000 | 47.465954 | SN2014J | archived | Jan 23 2014 12:03PM | Feb 3 2014 8:26PM | N | MARGUTTI |
15 | 200967 | 16577 | ACIS-S | NONE | 10.000000 | 9.964800 | KOI-314 | archived | Jan 21 2014 1:27PM | Feb 7 2014 9:42PM | D | Poppenhaeger |
14 | 401611 | 16563 | ACIS-I | NONE | 35.000000 | 32.061376 | PSRB1259-63 | archived | Dec 19 2013 4:13PM | Feb 8 2014 1:42PM | N | Pavlov |
14 | 401610 | 16561 | ACIS-S | NONE | 30.000000 | 30.578400 | XSSJ12270-4859 | archived | Dec 16 2013 1:33PM | Jan 11 2014 5:14AM | D | Patruno |
14 | 502268 | 16556 | ACIS-S | NONE | 20.000000 | 19.064984 | SN2013ge | archived | Dec 2 2013 12:21PM | Dec 7 2013 6:08PM | N | MARGUTTI |
14 | 502266 | 16488 | ACIS-S | NONE | 50.000000 | 46.073786 | GRB130925A | archived | Oct 1 2013 2:36PM | Oct 6 2013 4:22AM | D | Bellm |
14 | 502265 | 16441 | ACIS-S | NONE | 15.000000 | 15.069100 | GRB130831A | archived | Sep 9 2013 3:31PM | Oct 3 2013 1:27PM | D | DePasquale |
14 | 502264 | 16440 | ACIS-S | NONE | 15.000000 | 14.641300 | GRB130831A | archived | Sep 9 2013 3:31PM | Sep 17 2013 1:21AM | D | DePasquale |
14 | 502037 | 15663 | ACIS-S | NONE | 30.000000 | 29.964800 | GRB130606A | archived | Jun 12 2013 10:10AM | Jun 17 2013 3:29AM | D | Berger |
14 | 601099 | 15648 | ACIS-S | NONE | 25.000000 | 25.062680 | [SRW2012]Src.3c | archived | May 9 2013 3:19PM | May 24 2013 12:22PM | N | Roberts |
14 | 702923 | 15647 | ACIS-S | HETG | 30.000000 | 30.554400 | Mrk590 | archived | May 2 2013 9:55AM | Jun 16 2013 7:33AM | N | Mathur |
14 | 401541 | 15646 | ACIS-S | NONE | 15.000000 | 13.753555 | NGC404 | archived | Apr 26 2013 5:16PM | Jun 4 2013 2:44AM | N | Kaaret |
14 | 401540 | 15645 | HRC-S | NONE | 53.000000 | 53.041959 | IGRJ18245-2452 | archived | Apr 26 2013 10:08AM | Apr 29 2013 12:24AM | D | Patto |
14 | 100095 | 15641 | ACIS-S | NONE | 5.000000 | 5.183200 | Comet2011L4(PANST | archived | Mar 20 2013 4:41PM | Apr 24 2013 12:47AM | N | Lisse |
14 | 100094 | 15640 | ACIS-S | NONE | 5.000000 | 5.180100 | Comet2011L4(PANST | archived | Mar 20 2013 4:39PM | Apr 21 2013 2:39PM | N | Lisse |
14 | 100093 | 15639 | ACIS-S | NONE | 5.000000 | 5.177000 | Comet2011L4(PANST | archived | Mar 20 2013 4:38PM | Apr 17 2013 9:44AM | N | Lisse |
14 | 702922 | 15637 | ACIS-S | NONE | 15.000000 | 15.069100 | 2XMMIJ184725.1-6317 | archived | Mar 18 2013 5:51PM | Mar 29 2013 4:28AM | D | Lin |
14 | 100097 | 15631 | HRC-I | NONE | 5.000000 | 5.181632 | Comet2011L4(PANST | archived | Mar 14 2013 10:19PM | Apr 24 2013 2:21AM | N | Lisse |
14 | 100096 | 15630 | HRC-I | NONE | 5.000000 | 5.189832 | Comet2011L4(PANST | archived | Mar 14 2013 10:19PM | Apr 17 2013 11:17AM | N | Lisse |
14 | 100095 | 15629 | ACIS-S | NONE | 5.000000 | 5.071600 | Comet2011L4(PANST | archived | Mar 14 2013 10:19PM | Apr 23 2013 11:15PM | N | Lisse |
14 | 100094 | 15628 | ACIS-S | NONE | 5.000000 | 5.074700 | Comet2011L4(PANST | archived | Mar 14 2013 10:19PM | Apr 21 2013 1:07PM | N | Lisse |
14 | 100093 | 15627 | ACIS-S | NONE | 5.000000 | 5.070699 | Comet2011L4(PANST | archived | Mar 14 2013 10:19PM | Apr 17 2013 8:12AM | N | Lisse |
14 | 901095 | 15625 | ACIS-S | NONE | 10.000000 | 9.964770 | NuSTARJ163433-4738. | archived | Mar 11 2013 3:12PM | Mar 23 2013 8:46AM | D | Tomsick |
14 | 300318 | 15620 | HRC-I | NONE | 5.000000 | 5.179582 | M31N2013-01b | archived | Mar 1 2013 12:52PM | Mar 11 2013 11:16PM | N | Henze |
14 | 502032 | 15616 | ACIS-S | NONE | 2.000000 | 2.064600 | M82 | archived | Feb 11 2013 5:01PM | Feb 24 2013 11:25PM | N | Madej |
13 | 200910 | 15597 | ACIS-S | NONE | 25.000000 | 25.074440 | CRTSMLS121106J0144 | archived | Nov 19 2012 8:10PM | Nov 23 2012 5:02PM | D | Vianello |
13 | 300317 | 15596 | HRC-S | LETG | 25.000000 | 25.119933 | NovaMon2012 | archived | Nov 19 2012 2:11PM | Dec 3 2012 8:01PM | N | Orio |
13 | 702920 | 15584 | ACIS-S | NONE | 25.000000 | 24.966258 | SwiftJ1644+57 | archived | Nov 1 2012 10:24AM | Nov 26 2012 10:25AM | N | Tanvir |
13 | 300316 | 15495 | ACIS-S | HETG | 25.000000 | 25.049135 | PNVJ06393874+055352 | archived | Aug 29 2012 4:40PM | Sep 12 2012 9:13AM | N | Ness |
13 | 502021 | 15268 | ACIS-S | NONE | 20.000000 | 20.068815 | GRB120804A | archived | Aug 7 2012 2:47PM | Aug 13 2012 11:11AM | N | Troja |
13 | 502020 | 15265 | HRC-I | NONE | 10.000000 | 10.124182 | 1E2259+586 | archived | Jul 31 2012 12:04PM | Aug 21 2012 4:51PM | D | Kas |
13 | 501800 | 14464 | ACIS-S | NONE | 10.000000 | 10.068800 | GRB120624B | archived | Jun 28 2012 11:30AM | Jun 30 2012 9:24AM | N | Campana |
13 | 401435 | 14442 | ACIS-S | NONE | 20.000000 | 20.065073 | NGC4088 | archived | May 25 2012 4:51PM | Jun 2 2012 3:30AM | D | Mezcua |
13 | 401434 | 14441 | ACIS-S | HETG | 20.000000 | 19.073250 | 4U1630-47 | archived | May 24 2012 2:28PM | Jun 3 2012 10:28PM | D | Neilsen |
13 | 401430 | 14428 | ACIS-S | HETG | 20.000000 | 20.103500 | SwiftJ1753.5-0127 | archived | Apr 26 2012 12:18PM | May 3 2012 3:25PM | D | Soleri |
13 | 300312 | 14426 | HRC-S | LETG | 20.000000 | 20.189682 | NovaLMC2012 | archived | Apr 17 2012 6:34PM | Apr 26 2012 10:12PM | N | Drake |
13 | 401429 | 14425 | ACIS-S | HETG | 30.000000 | 30.088300 | MAXIJ1305-704 | archived | Apr 16 2012 2:32PM | Apr 29 2012 7:20PM | D | Miller |
13 | 501797 | 14420 | ACIS-S | NONE | 20.000000 | 20.398000 | PTF11qcj | archived | Mar 28 2012 2:18PM | Apr 11 2012 8:55AM | N | Corsi |
13 | 501796 | 14412 | ACIS-S | NONE | 40.000000 | 39.641600 | SN2011ja | archived | Mar 13 2012 2:26PM | Apr 3 2012 5:10AM | D | Ray |
13 | 200830 | 14402 | ACIS-S | NONE | 20.000000 | 20.069599 | 55Cnc | archived | Feb 23 2012 2:57PM | Apr 5 2012 1:03PM | D | Wheatley |
13 | 200829 | 14401 | ACIS-S | NONE | 12.000000 | 11.786399 | 55Cnc | archived | Feb 23 2012 2:56PM | Mar 7 2012 2:11AM | D | Wheatley |
13 | 501794 | 14398 | ACIS-S | NONE | 10.000000 | 10.062600 | PTF11qcj | archived | Feb 9 2012 12:09PM | Feb 26 2012 9:15AM | N | Corsi |
13 | 501793 | 14382 | ACIS-S | NONE | 10.000000 | 9.961085 | PTF11qcj | archived | Dec 27 2011 1:24PM | Jan 13 2012 1:43AM | N | Corsi |
13 | 401427 | 14376 | ACIS-S | NONE | 2.000000 | 2.010400 | NGC891ULX1 | archived | Dec 5 2011 4:45PM | Dec 20 2011 7:12AM | N | Hodges-Kluck |
13 | 501792 | 14360 | ACIS-S | NONE | 20.000000 | 21.010349 | CXOUJ164710.2-45521 | archived | Oct 12 2011 11:14AM | Oct 23 2011 3:56PM | D | Israel |
12 | 501791 | 14341 | ACIS-S | NONE | 40.000000 | 49.715200 | PTF11kly | archived | Aug 26 2011 10:09AM | Aug 27 2011 11:00AM | N | Hughes |
12 | 401425 | 14337 | ACIS-S | HETG | 14.000000 | 14.047270 | IGRJ17498-2921 | archived | Aug 24 2011 8:50AM | Aug 29 2011 2:22PM | N | DiSalvo |
12 | 401425 | 14336 | ACIS-S | HETG | 16.000000 | 16.345000 | IGRJ17498-2921 | archived | Aug 19 2011 3:02PM | Aug 30 2011 1:36PM | N | DiSalvo |
12 | 501789 | 14329 | ACIS-S | NONE | 15.000000 | 14.350399 | SwiftJ1834.9-0846 | archived | Aug 11 2011 2:56AM | Aug 22 2011 3:46PM | N | Kargaltsev |
12 | 501788 | 14237 | ACIS-S | NONE | 10.000000 | 10.043925 | GRB110709B | archived | Aug 3 2011 2:39PM | Oct 31 2011 8:15PM | N | Levan |
12 | 501567 | 13511 | HRC-I | NONE | 1.000000 | 1.181953 | SwiftJ1822.3-1606 | archived | Jul 18 2011 2:48PM | Jul 28 2011 8:21PM | D | Kouveliotou |
12 | 702582 | 13423 | HRC-I | NONE | 5.000000 | 5.187525 | SWIFTJ2058.4+0516 | archived | Jun 13 2011 12:57PM | Jun 22 2011 3:04PM | N | Cenko |
12 | 401300 | 13420 | HRC-I | NONE | 1.000000 | 1.530581 | M15 | archived | May 18 2011 4:15PM | May 30 2011 4:54PM | N | Sivakoff |
12 | 501563 | 13419 | ACIS-S | NONE | 5.000000 | 5.043424 | SNRG306.3-0.9 | archived | May 6 2011 2:58PM | Jun 2 2011 2:06PM | N | Miller |
12 | 702581 | 13418 | ACIS-S | NONE | 10.000000 | 10.040058 | PS1-10jh | archived | Apr 29 2011 10:54AM | May 22 2011 11:16PM | N | Gezari |
12 | 401297 | 13252 | ACIS-S | NONE | 40.000000 | 40.080000 | PSRJ1748-2446am | archived | Mar 31 2011 10:28AM | Apr 29 2011 5:30PM | D | Degenaar |
12 | 200735 | 13250 | ACIS-S | LETG | 20.000000 | 20.075300 | TWHya | archived | Mar 29 2011 4:23PM | Apr 13 2011 12:00PM | N | Guenther |
12 | 401295 | 13237 | ACIS-S | NONE | 40.000000 | 40.077250 | HESSJ0632+057 | archived | Feb 9 2011 2:40PM | Feb 13 2011 9:28PM | D | Torres |
12 | 401293 | 13225 | ACIS-S | NONE | 30.000000 | 30.078000 | PSRJ1748-2446am | archived | Jan 24 2011 2:02PM | Feb 17 2011 9:31AM | D | Wijnands |
12 | 401292 | 13219 | ACIS-S | HETG | 12.000000 | 12.000000 | CygX-1 | archived | Jan 19 2011 9:47AM | Feb 5 2011 6:56AM | N | McClintock |
12 | 501549 | 13217 | ACIS-S | NONE | 15.000000 | 15.010343 | XTEJ1810-197 | archived | Jan 12 2011 12:23AM | Feb 9 2011 12:04AM | D | Perna |
12 | 600982 | 13212 | ACIS-S | NONE | 10.000000 | 10.186400 | NGC1589-OT | archived | Dec 23 2010 3:54PM | Jan 16 2011 3:58AM | N | Filippenko |
12 | 501548 | 13210 | ACIS-S | NONE | 5.000000 | 5.000000 | Crab | archived | Dec 14 2010 12:26PM | Oct 15 2011 4:51AM | N | Weisskopf |
12 | 501547 | 13209 | ACIS-S | NONE | 5.000000 | 5.000000 | Crab | archived | Dec 14 2010 12:26PM | Sep 15 2011 4:09AM | N | Weisskopf |
12 | 501546 | 13208 | ACIS-S | NONE | 5.000000 | 5.000000 | Crab | archived | Dec 14 2010 12:26PM | Aug 15 2011 9:01AM | N | Weisskopf |
12 | 501545 | 13207 | ACIS-S | NONE | 5.000000 | 5.000000 | Crab | archived | Dec 14 2010 12:26PM | Apr 12 2011 2:15PM | N | Weisskopf |
12 | 501544 | 13206 | ACIS-S | NONE | 5.000000 | 5.000000 | Crab | archived | Dec 14 2010 12:26PM | Mar 15 2011 6:04AM | N | Weisskopf |
12 | 501543 | 13205 | ACIS-S | NONE | 5.000000 | 5.000000 | Crab | archived | Dec 14 2010 12:26PM | Feb 16 2011 4:52PM | N | Weisskopf |
12 | 501542 | 13204 | ACIS-S | NONE | 5.000000 | 3.323628 | Crab | archived | Dec 14 2010 12:26PM | Jan 15 2011 12:07AM | N | Weisskopf |
12 | 702511 | 13203 | ACIS-S | NONE | 16.000000 | 16.046587 | ULASJ1120+0641 | archived | Dec 13 2010 12:51PM | Feb 4 2011 12:08PM | D | Simpson |
12 | 401291 | 13171 | ACIS-S | NONE | 4.000000 | 3.755348 | 1RXSJ192430.2+51014 | archived | Oct 20 2010 9:21AM | Nov 7 2010 7:58AM | D | Liu |
12 | 401290 | 13170 | ACIS-S | NONE | 4.000000 | 3.961600 | 1RXSJ194016.3+46325 | archived | Oct 20 2010 9:21AM | Nov 7 2010 2:06PM | D | Liu |
12 | 401289 | 13169 | ACIS-S | NONE | 3.000000 | 2.965220 | 1RXSJ192607.1+50525 | archived | Oct 20 2010 9:20AM | Nov 12 2010 4:16PM | D | Liu |
12 | 401288 | 13168 | ACIS-S | NONE | 3.000000 | 2.962514 | 1RXSJ190822.7+38510 | archived | Oct 20 2010 9:20AM | Nov 12 2010 7:57PM | D | Liu |
12 | 401287 | 13167 | ACIS-S | NONE | 3.000000 | 2.960000 | 1RXSJ191016.9+39295 | archived | Oct 20 2010 9:20AM | Nov 7 2010 6:52AM | D | Liu |
12 | 401286 | 13166 | ACIS-S | NONE | 3.000000 | 2.752000 | 1RXSJ193239.6+38251 | archived | Oct 20 2010 9:20AM | Nov 4 2010 9:49PM | D | Liu |
12 | 401285 | 13165 | ACIS-S | NONE | 3.000000 | 2.758400 | 1RXSJ192630.6+41331 | archived | Oct 20 2010 9:20AM | Nov 4 2010 10:50PM | D | Liu |
12 | 401284 | 13164 | ACIS-S | NONE | 2.000000 | 2.097700 | 1RXSJ194759.9+41311 | archived | Oct 20 2010 9:20AM | Nov 14 2010 3:12AM | D | Liu |
12 | 401283 | 13163 | ACIS-S | NONE | 2.000000 | 2.097586 | 1RXSJ191438.6+50285 | archived | Oct 20 2010 9:20AM | Nov 7 2010 1:05PM | D | Liu |
12 | 401282 | 13161 | ACIS-S | HETG | 30.000000 | 30.074000 | EXO1745-248 | archived | Oct 15 2010 12:44PM | Oct 24 2010 11:03AM | D | Bhattacharyya |
12 | 501540 | 13154 | ACIS-S | NONE | 10.000000 | 10.000000 | CrabNebula | archived | Oct 7 2010 11:57AM | Apr 28 2011 6:40AM | N | Weisskopf |
12 | 501539 | 13153 | ACIS-S | NONE | 10.000000 | 10.000000 | CrabNebula | archived | Oct 7 2010 11:57AM | Apr 21 2011 11:25PM | N | Weisskopf |
12 | 501538 | 13152 | ACIS-S | NONE | 10.000000 | 10.000000 | CrabNebula | archived | Oct 7 2010 11:57AM | Apr 16 2011 8:45AM | N | Weisskopf |
12 | 501537 | 13151 | ACIS-S | NONE | 10.000000 | 10.000000 | CrabNebula | archived | Oct 7 2010 11:57AM | Apr 14 2011 2:32PM | N | Weisskopf |
12 | 501536 | 13150 | ACIS-S | NONE | 10.000000 | 10.000000 | CrabNebula | archived | Oct 7 2010 11:57AM | Apr 13 2011 11:32PM | N | Weisskopf |
12 | 501535 | 13149 | ACIS-S | NONE | 15.000000 | 15.459500 | XTEJ1810-197 | archived | Oct 7 2010 10:30AM | Oct 25 2010 4:19AM | D | Bernardini |
12 | 501534 | 13148 | ACIS-S | NONE | 30.000000 | 30.009912 | SGR0418+5729 | archived | Oct 6 2010 4:04PM | Nov 29 2010 6:10AM | N | Rea |
12 | 501533 | 13147 | ACIS-S | NONE | 5.000000 | 5.000000 | Crab | archived | Oct 5 2010 4:26PM | Nov 28 2010 11:17AM | N | ferrigno |
12 | 501532 | 13146 | ACIS-S | NONE | 5.000000 | 5.000000 | Crab | archived | Oct 5 2010 4:26PM | Oct 28 2010 5:58PM | N | ferrigno |
11 | 501531 | 13139 | ACIS-S | NONE | 5.000000 | 5.000000 | CrabNebula | archived | Sep 23 2010 3:29PM | Sep 28 2010 5:21AM | N | Weisskopf |
11 | 401281 | 13122 | ACIS-S | NONE | 10.000000 | 10.026400 | ESO243-49HLX-1 | archived | Sep 1 2010 9:49AM | Sep 6 2010 10:40PM | D | Farrell |
11 | 401145 | 12314 | ACIS-S | HETG | 6.000000 | 6.000000 | CygX-1 | archived | Jul 14 2010 10:31AM | Jul 24 2010 5:38PM | N | McClintock |
11 | 401144 | 12313 | ACIS-S | HETG | 6.000000 | 6.072000 | CygX-1 | archived | Jul 14 2010 10:31AM | Jul 22 2010 4:39PM | N | McClintock |
11 | 501371 | 12312 | ACIS-S | NONE | 30.000000 | 30.009198 | SGR0418+5729 | archived | Jul 12 2010 10:28AM | Jul 23 2010 3:16PM | N | Rea |
11 | 401141 | 12235 | ACIS-S | HETG | 20.000000 | 20.079600 | CirX-1 | archived | Jun 29 2010 5:24PM | Jul 4 2010 5:22AM | N | D'A |
09 | 900939 | 12234 | ACIS-I | NONE | 53.000000 | 49.800438 | ChandraDeepFieldS | archived | Jun 25 2010 4:49PM | Jul 22 2010 8:13PM | 4 | Tananbaum |
09 | 900939 | 12233 | ACIS-I | NONE | 35.000000 | 36.043659 | ChandraDeepFieldS | archived | Jun 25 2010 4:48PM | Jul 16 2010 10:52AM | 4 | Tananbaum |
09 | 900939 | 12232 | ACIS-I | NONE | 34.000000 | 33.329777 | ChandraDeepFieldS | archived | Jun 25 2010 4:45PM | Jul 18 2010 8:09PM | 4 | Tananbaum |
09 | 900939 | 12231 | ACIS-I | NONE | 25.000000 | 25.047959 | ChandraDeepFieldS | archived | Jun 23 2010 11:40AM | Jul 12 2010 3:49AM | 4 | Tananbaum |
09 | 900939 | 12230 | ACIS-I | NONE | 38.000000 | 34.254918 | ChandraDeepFieldS | archived | Jun 20 2010 2:29PM | Jul 11 2010 4:18AM | 4 | Tananbaum |
11 | 501369 | 12229 | ACIS-S | NONE | 15.000000 | 15.037309 | GRB100615A | archived | Jun 16 2010 3:07PM | Jun 21 2010 3:52AM | N | Levan |
09 | 900939 | 12227 | ACIS-I | NONE | 55.000000 | 55.043411 | ChandraDeepFieldS | archived | Jun 10 2010 12:06PM | Jul 14 2010 9:28PM | 4 | Tananbaum |
09 | 900938 | 12223 | ACIS-I | NONE | 102.000000 | 102.041441 | ChandraDeepFieldS | archived | May 26 2010 4:55PM | Jun 13 2010 1:21AM | 4 | Tananbaum |
09 | 900938 | 12222 | ACIS-I | NONE | 31.000000 | 31.049146 | ChandraDeepFieldS | archived | May 26 2010 4:10PM | Jun 5 2010 3:09AM | 4 | Tananbaum |
11 | 501368 | 12221 | ACIS-S | NONE | 10.000000 | 10.065300 | XTEJ1810-197 | archived | May 21 2010 11:36AM | Jun 7 2010 3:29AM | D | Bernardini |
09 | 900938 | 12220 | ACIS-I | NONE | 48.900000 | 48.768154 | ChandraDeepFieldS | archived | May 18 2010 8:29AM | Jun 18 2010 1:16PM | 4 | Tananbaum |
09 | 900938 | 12219 | ACIS-I | NONE | 34.200000 | 34.106014 | ChandraDeepFieldS | archived | May 18 2010 8:20AM | Jun 6 2010 4:49PM | 4 | Tananbaum |
09 | 900938 | 12218 | ACIS-I | NONE | 89.200000 | 89.142158 | ChandraDeepFieldS | archived | May 12 2010 5:03PM | Jun 11 2010 10:33AM | 4 | Tananbaum |
09 | 900936 | 12213 | ACIS-I | NONE | 62.100000 | 62.098441 | ChandraDeepFieldS | archived | Apr 28 2010 3:10PM | May 17 2010 2:55PM | 4 | Tananbaum |
11 | 300283 | 12203 | HRC-S | LETG | 5.000000 | 5.181632 | KTEri | archived | Apr 9 2010 2:19PM | Apr 21 2010 11:03AM | N | Drake |
09 | 900937 | 12138 | ACIS-I | NONE | 39.000000 | 39.044418 | ChandraDeepFieldS | archived | Mar 30 2010 8:19AM | Apr 18 2010 1:16PM | 4 | Tananbaum |
09 | 900937 | 12137 | ACIS-I | NONE | 94.000000 | 94.010314 | ChandraDeepFieldS | archived | Mar 30 2010 8:19AM | Apr 16 2010 9:10AM | 4 | Tananbaum |
09 | 900937 | 12135 | ACIS-I | NONE | 63.400000 | 63.357678 | ChandraDeepFieldS | archived | Mar 25 2010 3:35PM | Apr 6 2010 9:50AM | 4 | Tananbaum |
09 | 900937 | 12129 | ACIS-I | NONE | 78.200000 | 78.160096 | ChandraDeepFieldS | archived | Mar 17 2010 10:54AM | Apr 3 2010 3:40PM | 4 | Tananbaum |
09 | 900936 | 12128 | ACIS-I | NONE | 23.100000 | 23.104259 | ChandraDeepFieldS | archived | Mar 9 2010 4:02PM | Mar 27 2010 1:28PM | 4 | Tananbaum |
11 | 401138 | 12127 | ACIS-S | HETG | 25.000000 | 23.167750 | 4U1608-52 | archived | Mar 8 2010 4:25PM | Mar 15 2010 4:46AM | N | Ozel |
09 | 900936 | 12123 | ACIS-I | NONE | 25.100000 | 25.118041 | ChandraDeepFieldS | archived | Mar 4 2010 3:45PM | Mar 21 2010 8:23AM | 4 | Tananbaum |
11 | 300277 | 12102 | HRC-S | LETG | 25.000000 | 23.244182 | UScorpii | archived | Jan 28 2010 12:11PM | Feb 14 2010 11:56AM | N | Orio |
11 | 300276 | 12101 | HRC-S | LETG | 5.000000 | 5.158825 | KTEri | archived | Jan 26 2010 9:26AM | Feb 6 2010 6:43AM | N | Drake |
11 | 300275 | 12100 | HRC-S | LETG | 5.000000 | 5.181375 | KTEri | archived | Jan 26 2010 9:26AM | Jan 31 2010 10:43PM | N | Drake |
11 | 300274 | 12097 | HRC-S | LETG | 15.000000 | 15.183582 | KTEri | archived | Jan 20 2010 12:33PM | Jan 23 2010 10:01PM | N | Ness |
11 | 702317 | 12087 | ACIS-S | NONE | 3.000000 | 3.061700 | Q0957+561 | archived | Dec 22 2009 2:14PM | Jun 23 2010 11:29PM | N | Goicoechea |
11 | 702316 | 12086 | ACIS-S | NONE | 3.000000 | 3.062981 | Q0957+561 | archived | Dec 22 2009 2:13PM | Jun 10 2010 10:14AM | N | Goicoechea |
11 | 702315 | 12085 | ACIS-S | NONE | 3.000000 | 3.061700 | Q0957+561 | archived | Dec 22 2009 2:13PM | May 25 2010 11:08PM | N | Goicoechea |
11 | 702314 | 12084 | ACIS-S | NONE | 3.000000 | 3.182400 | Q0957+561 | archived | Dec 22 2009 2:13PM | May 15 2010 4:53AM | N | Goicoechea |
11 | 702313 | 12083 | ACIS-S | NONE | 3.000000 | 3.151800 | Q0957+561 | archived | Dec 22 2009 2:12PM | Apr 27 2010 1:21PM | N | Goicoechea |
11 | 702312 | 12082 | ACIS-S | NONE | 3.000000 | 3.182400 | Q0957+561 | archived | Dec 22 2009 2:12PM | Apr 13 2010 1:14PM | N | Goicoechea |
11 | 702311 | 12081 | ACIS-S | NONE | 3.000000 | 3.170500 | Q0957+561 | archived | Dec 22 2009 2:11PM | Mar 29 2010 9:43PM | N | Goicoechea |
11 | 702310 | 12080 | ACIS-S | NONE | 3.000000 | 3.126300 | Q0957+561 | archived | Dec 22 2009 2:11PM | Mar 15 2010 12:00PM | N | Goicoechea |
11 | 702309 | 12079 | ACIS-S | NONE | 3.000000 | 3.150100 | Q0957+561 | archived | Dec 22 2009 2:11PM | Mar 3 2010 2:58PM | N | Goicoechea |
11 | 702308 | 12078 | ACIS-S | NONE | 3.000000 | 3.182400 | Q0957+561 | archived | Dec 22 2009 2:10PM | Feb 18 2010 6:43AM | N | Goicoechea |
11 | 702307 | 12077 | ACIS-S | NONE | 3.000000 | 3.185800 | Q0957+561 | archived | Dec 22 2009 2:10PM | Feb 1 2010 12:50AM | N | Goicoechea |
11 | 702306 | 12076 | ACIS-S | NONE | 3.000000 | 3.060000 | Q0957+561 | archived | Dec 22 2009 1:57PM | Jan 17 2010 12:56PM | N | Goicoechea |
10 | 401137 | 12067 | ACIS-S | HETG | 11.000000 | 11.081250 | 1A0535+262 | archived | Dec 15 2009 1:14PM | Dec 31 2009 2:19AM | D | Reynolds |
10 | 401137 | 12066 | ACIS-S | HETG | 9.000000 | 8.917250 | 1A0535+262 | archived | Dec 10 2009 2:59AM | Dec 28 2009 11:08AM | D | Reynolds |
09 | 900936 | 12055 | ACIS-I | NONE | 81.800000 | 81.749978 | ChandraDeepFieldS | archived | Nov 24 2009 3:21PM | May 15 2010 5:35PM | 4 | Tananbaum |
09 | 900939 | 12054 | ACIS-I | NONE | 62.000000 | 61.810778 | ChandraDeepFieldS | archived | Nov 24 2009 3:21PM | Jul 9 2010 12:02PM | 4 | Tananbaum |
09 | 900939 | 12053 | ACIS-I | NONE | 75.000000 | 69.009060 | ChandraDeepFieldS | archived | Nov 24 2009 3:21PM | Jul 5 2010 3:30AM | 4 | Tananbaum |
09 | 900939 | 12052 | ACIS-I | NONE | 112.600000 | 111.875500 | ChandraDeepFieldS | archived | Nov 24 2009 3:21PM | Jun 15 2010 4:32PM | 4 | Tananbaum |
09 | 900938 | 12051 | ACIS-I | NONE | 58.000000 | 58.044247 | ChandraDeepFieldS | archived | Nov 24 2009 3:21PM | Jun 10 2010 11:57AM | 4 | Tananbaum |
09 | 900938 | 12050 | ACIS-I | NONE | 30.000000 | 30.048259 | ChandraDeepFieldS | archived | Nov 24 2009 3:21PM | Jun 3 2010 7:03AM | 4 | Tananbaum |
09 | 900938 | 12049 | ACIS-I | NONE | 88.000000 | 88.088925 | ChandraDeepFieldS | archived | Nov 24 2009 3:21PM | May 28 2010 7:18PM | 4 | Tananbaum |
09 | 900937 | 12048 | ACIS-I | NONE | 140.000000 | 139.932947 | ChandraDeepFieldS | archived | Nov 24 2009 3:21PM | May 23 2010 7:26AM | 4 | Tananbaum |
09 | 900937 | 12047 | ACIS-I | NONE | 10.300000 | 10.276459 | ChandraDeepFieldS | archived | Nov 24 2009 3:21PM | Apr 12 2010 1:47PM | 4 | Tananbaum |
09 | 900937 | 12046 | ACIS-I | NONE | 79.000000 | 79.056119 | ChandraDeepFieldS | archived | Nov 24 2009 3:21PM | Apr 8 2010 8:31AM | 4 | Tananbaum |
09 | 900937 | 12045 | ACIS-I | NONE | 101.000000 | 101.037949 | ChandraDeepFieldS | archived | Nov 24 2009 3:21PM | Mar 28 2010 4:58PM | 4 | Tananbaum |
09 | 900936 | 12044 | ACIS-I | NONE | 100.800000 | 100.842837 | ChandraDeepFieldS | archived | Nov 24 2009 3:21PM | Mar 23 2010 11:55AM | 4 | Tananbaum |
09 | 900936 | 12043 | ACIS-I | NONE | 131.300000 | 131.294013 | ChandraDeepFieldS | archived | Nov 24 2009 3:21PM | Mar 18 2010 1:58AM | 4 | Tananbaum |
10 | 200656 | 12009 | ACIS-S | NONE | 25.000000 | 24.473600 | V838Mon | archived | Oct 13 2009 10:58AM | Jan 12 2010 8:44AM | N | Kastner |
10 | 401125 | 11803 | HRC-I | NONE | 10.000000 | 10.156982 | ESO243-49HLX-1 | archived | Aug 10 2009 5:46PM | Aug 17 2009 12:41PM | N | Farrell |
10 | 401124 | 11802 | ACIS-S | NONE | 5.000000 | 5.035200 | NGC6440 | archived | Aug 4 2009 6:03PM | Aug 10 2009 8:26AM | N | Heinke |
10 | 501174 | 10929 | ACIS-I | NONE | 20.000000 | 20.134400 | PSRJ1622-4950 | archived | Jul 8 2009 9:03AM | Jul 10 2009 7:43AM | 3 | Rea |
10 | 701973 | 10921 | ACIS-S | NONE | 5.000000 | 5.046400 | 2XMMJ130200.1+27465 | archived | Jun 3 2009 12:08PM | Jun 27 2009 3:28AM | N | Watson |
10 | 401066 | 10919 | HRC-I | NONE | 1.000000 | 1.175675 | ESO243-49HLX-1 | archived | May 29 2009 1:38PM | Jul 4 2009 2:15PM | N | Farrell |
10 | 401065 | 10907 | ACIS-S | NONE | 20.000000 | 18.448100 | GROJ1655-40 | archived | Apr 17 2009 5:40PM | Jun 8 2009 2:46AM | N | Gallo |
09 | 200569 | 10845 | ACIS-S | NONE | 40.000000 | 40.134400 | ZCMa | archived | Dec 18 2008 11:19AM | Dec 28 2008 10:48PM | N | Stelzer |
09 | 200568 | 10826 | HRC-I | NONE | 5.000000 | 4.978425 | 51Peg | archived | Nov 17 2008 8:51AM | Dec 6 2008 12:52PM | N | Schmitt |
09 | 200568 | 10825 | ACIS-S | NONE | 5.000000 | 4.982400 | 51Peg | archived | Nov 17 2008 8:45AM | Dec 6 2008 11:21AM | N | Schmitt |
09 | 401051 | 10574 | HRC-I | NONE | 5.000000 | 5.162669 | XTEJ1701-407 | archived | Aug 18 2008 3:29PM | Aug 26 2008 8:24PM | D | Kaplan |
09 | 501152 | 10573 | ACIS-S | NONE | 10.000000 | 10.152500 | GRB080307 | archived | Aug 14 2008 5:07PM | Sep 22 2008 8:36AM | N | Page |
09 | 401050 | 10571 | HRC-I | NONE | 1.000000 | 1.183875 | VPuppis | archived | Aug 7 2008 2:56PM | Sep 1 2008 1:40AM | N | Maccarone |
09 | 400934 | 9883 | ACIS-S | NONE | 10.000000 | 10.198400 | XMMUJ005510.7-37385 | archived | Jun 25 2008 2:22AM | Jul 8 2008 9:26PM | N | Kong |
09 | 400933 | 9882 | ACIS-S | NONE | 30.000000 | 30.180000 | AXJ1754.2-2754 | archived | Jun 24 2008 3:23PM | Jul 15 2008 12:30AM | D | Keek |
09 | 501018 | 9862 | ACIS-S | NONE | 30.000000 | 30.147200 | GRB080503 | archived | May 16 2008 4:13PM | May 25 2008 6:28PM | N | Butler |
09 | 501017 | 9853 | ACIS-S | NONE | 30.000000 | 30.175400 | GRB080503 | archived | May 5 2008 9:16PM | May 7 2008 7:35PM | N | Butler |
09 | 400932 | 9850 | HRC-I | NONE | 2.000000 | 2.186069 | XTEJ1719-291 | archived | Apr 15 2008 8:53AM | Apr 27 2008 6:34PM | D | Sala |
09 | 701771 | 9814 | ACIS-S | NONE | 10.000000 | 9.907200 | SDSSJ0952+2143 | archived | Jan 23 2008 8:44AM | Feb 5 2008 4:43PM | N | Komossa |
09 | 400931 | 9805 | ACIS-S | NONE | 5.000000 | 5.175000 | M81 | archived | Dec 19 2007 2:43PM | Dec 21 2007 6:54PM | D | Jonker |
09 | 501014 | 9799 | ACIS-S | NONE | 21.500000 | 21.569800 | SN2007on | archived | Dec 12 2007 3:41PM | Dec 27 2007 1:35AM | D | Roelofs |
09 | 501014 | 9798 | ACIS-S | NONE | 18.500000 | 18.544200 | SN2007on | archived | Dec 5 2007 3:21PM | Dec 24 2007 11:15AM | D | Roelofs |
09 | 200526 | 9769 | ACIS-I | NONE | 30.000000 | 30.150559 | NGC2264 | archived | Nov 9 2007 4:15PM | Mar 28 2008 3:02PM | N | Micela |
09 | 200526 | 9768 | ACIS-I | NONE | 30.000000 | 28.154200 | NGC2264 | archived | Nov 9 2007 4:08PM | Mar 12 2008 6:10PM | N | Micela |
08 | 100071 | 9763 | ACIS-S | NONE | 10.000000 | 10.179200 | Comet17P/Holmes | archived | Oct 29 2007 1:32PM | Oct 31 2007 4:21PM | N | Dennerl |
08 | 100071 | 9762 | ACIS-S | NONE | 10.000000 | 10.188800 | Comet17P/Holmes | archived | Oct 29 2007 1:32PM | Oct 31 2007 1:26PM | N | Dennerl |
08 | 100071 | 9755 | ACIS-S | NONE | 10.000000 | 10.137600 | Comet17P/Holmes | archived | Oct 26 2007 4:43PM | Oct 31 2007 10:31AM | N | Dennerl |
08 | 900737 | 9718 | ACIS-I | NONE | 51.000000 | 50.030737 | ChandraDeepFieldS | archived | Sep 19 2007 3:00PM | Oct 3 2007 2:12PM | N | Tananbaum |
08 | 900737 | 9596 | ACIS-I | NONE | 115.400000 | 113.372872 | ChandraDeepFieldS | archived | Sep 10 2007 3:32PM | Nov 4 2007 4:30AM | N | Tananbaum |
08 | 900737 | 9593 | ACIS-I | NONE | 48.000000 | 47.045600 | ChandraDeepFieldS | archived | Sep 5 2007 12:11PM | Sep 22 2007 8:49PM | N | Tananbaum |
08 | 400928 | 9584 | HRC-I | NONE | 2.000000 | 2.184531 | M15 | archived | Aug 27 2007 11:51AM | Sep 5 2007 3:23PM | N | Heinke |
08 | 501009 | 9579 | ACIS-I | NONE | 20.000000 | 19.709759 | SN2007gr | archived | Aug 21 2007 1:16PM | Aug 29 2007 1:52AM | N | Soderberg |
08 | 900737 | 9578 | ACIS-I | NONE | 40.000000 | 39.084800 | ChandraDeepFieldS | archived | Aug 20 2007 4:20PM | Oct 30 2007 10:53PM | N | Tananbaum |
08 | 900737 | 9575 | ACIS-I | NONE | 112.400000 | 110.133372 | ChandraDeepFieldS | archived | Aug 20 2007 4:18PM | Oct 27 2007 6:09AM | N | Tananbaum |
08 | 900737 | 8597 | ACIS-I | NONE | 61.000000 | 60.068618 | ChandraDeepFieldS | archived | Aug 7 2007 3:31PM | Oct 17 2007 7:23AM | N | Tananbaum |
08 | 900737 | 8596 | ACIS-I | NONE | 118.000000 | 116.640477 | ChandraDeepFieldS | archived | Aug 7 2007 3:31PM | Oct 24 2007 1:46PM | N | Tananbaum |
08 | 900737 | 8595 | ACIS-I | NONE | 118.000000 | 116.950436 | ChandraDeepFieldS | archived | Aug 7 2007 3:31PM | Oct 19 2007 2:35PM | N | Tananbaum |
08 | 900737 | 8594 | ACIS-I | NONE | 151.200000 | 143.272414 | ChandraDeepFieldS | archived | Aug 7 2007 3:31PM | Nov 1 2007 12:10PM | N | Tananbaum |
08 | 900737 | 8593 | ACIS-I | NONE | 51.000000 | 50.145559 | ChandraDeepFieldS | archived | Aug 7 2007 3:31PM | Oct 6 2007 2:22AM | N | Tananbaum |
08 | 900737 | 8592 | ACIS-I | NONE | 88.000000 | 87.785596 | ChandraDeepFieldS | archived | Aug 7 2007 3:31PM | Oct 22 2007 12:36PM | N | Tananbaum |
08 | 900737 | 8591 | ACIS-I | NONE | 46.000000 | 46.034877 | ChandraDeepFieldS | archived | Aug 7 2007 3:31PM | Sep 20 2007 5:41AM | N | Tananbaum |
08 | 400691 | 8564 | ACIS-I | NONE | 11.200000 | 11.152000 | SWIFTJ1756.9-2508 | archived | Jun 19 2007 12:29PM | Jul 6 2007 1:44AM | N | DiSalvo |
08 | 400690 | 8562 | ACIS-S | HETG | 10.000000 | 10.152500 | SWIFTJ195509.6+2614 | archived | Jun 12 2007 1:01PM | Jun 14 2007 6:17PM | D | KANBACH |
08 | 400689 | 8556 | HRC-I | NONE | 7.000000 | 7.180382 | CirX-1 | archived | Apr 27 2007 3:09PM | May 16 2007 9:11PM | D | Jonker |
08 | 400688 | 8547 | HRC-I | NONE | 43.000000 | 43.290108 | CirX-1 | archived | Mar 30 2007 1:52PM | Apr 21 2007 5:32AM | D | Jonker |
08 | 600649 | 8524 | ACIS-S | NONE | 30.000000 | 30.041600 | GRB070125 | archived | Feb 22 2007 9:56AM | Mar 5 2007 9:49PM | N | Frail |
08 | 500822 | 8518 | ACIS-S | NONE | 3.000000 | 3.043200 | SN2005kd | archived | Jan 30 2007 2:09PM | Mar 4 2007 2:54PM | N | Pooley |
08 | 701583 | 8517 | ACIS-S | NONE | 5.000000 | 5.153200 | M87 | archived | Jan 26 2007 3:19PM | Mar 22 2007 4:06AM | N | Harris |
08 | 701582 | 8516 | ACIS-S | NONE | 5.000000 | 5.159200 | M87 | archived | Jan 26 2007 3:19PM | Mar 19 2007 10:38AM | N | Harris |
08 | 701581 | 8515 | ACIS-S | NONE | 5.000000 | 5.177600 | M87 | archived | Jan 26 2007 3:19PM | Mar 14 2007 2:43PM | N | Harris |
08 | 701580 | 8514 | ACIS-S | NONE | 5.000000 | 4.929200 | M87 | archived | Jan 26 2007 3:19PM | Mar 12 2007 11:52AM | N | Harris |
08 | 701579 | 8513 | ACIS-S | NONE | 5.000000 | 5.182800 | M87 | archived | Jan 26 2007 3:19PM | Feb 24 2007 3:16AM | N | Harris |
08 | 701578 | 8512 | ACIS-S | NONE | 5.000000 | 5.185600 | M87 | archived | Jan 26 2007 3:19PM | Feb 21 2007 11:58PM | N | Harris |
08 | 701577 | 8511 | ACIS-S | NONE | 5.000000 | 5.185600 | M87 | archived | Jan 26 2007 3:19PM | Feb 18 2007 10:23PM | N | Harris |
08 | 701576 | 8510 | ACIS-S | NONE | 5.000000 | 5.183600 | M87 | archived | Jan 26 2007 3:19PM | Feb 15 2007 9:37AM | N | Harris |
08 | 500821 | 8508 | HRC-I | NONE | 2.000000 | 2.159931 | 1RXSJ141256.0+79220 | archived | Jan 19 2007 12:55PM | Feb 18 2007 6:05PM | D | Rutledge |
08 | 500820 | 8506 | ACIS-S | NONE | 20.000000 | 20.182000 | PSRJ1647-4552 | archived | Jan 8 2007 1:10PM | Feb 2 2007 7:26PM | N | Woods |
07 | 500817 | 8480 | HRC-I | NONE | 1.000000 | 1.149025 | RBS1774(1RXSJ214303 | archived | Nov 6 2006 2:27PM | Nov 26 2006 10:15PM | D | Zane |
07 | 200460 | 8474 | ACIS-I | NONE | 10.000000 | 9.753600 | LDN1415 | archived | Oct 30 2006 11:32AM | Nov 18 2006 2:41AM | N | Kastner |
07 | 500816 | 8473 | ACIS-S | NONE | 30.000000 | 30.124800 | SN2006gy | archived | Oct 30 2006 11:20AM | Nov 14 2006 8:57PM | N | Pooley |
07 | 500815 | 8457 | ACIS-S | NONE | 10.000000 | 9.961600 | SN2006jc | archived | Oct 16 2006 12:14PM | Nov 4 2006 6:23AM | N | Immler |
07 | 500814 | 8455 | ACIS-S | NONE | 15.000000 | 15.186750 | PSRJ1647-4552 | archived | Oct 12 2006 12:50PM | Oct 28 2006 7:19AM | D | Kas |
07 | 400680 | 8273 | ACIS-I | NONE | 21.600000 | 20.030359 | LSI+61303 | archived | Sep 8 2006 3:29PM | Oct 25 2006 10:32PM | N | Perez-Torres |
07 | 600607 | 7373 | ACIS-S | NONE | 7.000000 | 7.184000 | XMMUJ132218.3-16424 | archived | Jul 12 2006 5:56PM | Jul 31 2006 3:41AM | N | Miniutti |
07 | 400561 | 7335 | ACIS-S | NONE | 10.000000 | 9.376000 | PSRB1931+24 | archived | May 5 2006 2:30PM | Jul 20 2006 3:01PM | D | Rea |
07 | 100067 | 7334 | ACIS-S | NONE | 4.000000 | 4.182400 | Comet73P/Schwassman | archived | May 2 2006 2:32PM | May 23 2006 10:34AM | N | Wolk |
07 | 100066 | 7333 | ACIS-S | NONE | 4.000000 | 4.182400 | Comet73P/Schwassman | archived | May 2 2006 2:32PM | May 23 2006 9:19AM | N | Wolk |
07 | 100065 | 7332 | ACIS-S | NONE | 4.000000 | 4.185600 | Comet73P/Schwassman | archived | May 2 2006 2:32PM | May 23 2006 8:03AM | N | Wolk |
07 | 100064 | 7331 | ACIS-S | NONE | 4.000000 | 4.185600 | Comet73P/Schwassman | archived | May 2 2006 2:32PM | May 23 2006 6:48AM | N | Wolk |
07 | 100063 | 7330 | ACIS-S | NONE | 4.000000 | 4.105600 | Comet73P/Schwassman | archived | May 2 2006 2:32PM | May 23 2006 5:33AM | N | Wolk |
07 | 300179 | 7298 | HRC-S | LETG | 20.000000 | 20.126132 | RSOph | archived | Mar 3 2006 1:28PM | Jun 4 2006 12:25PM | N | Starrfield |
07 | 300178 | 7297 | HRC-S | LETG | 10.000000 | 9.505082 | RSOph | archived | Mar 3 2006 1:28PM | Apr 20 2006 5:43PM | N | Starrfield |
07 | 300177 | 7296 | HRC-S | LETG | 10.000000 | 10.152882 | RSOph | archived | Mar 3 2006 1:28PM | Mar 24 2006 12:40PM | N | Starrfield |
07 | 300172 | 7280 | ACIS-S | HETG | 10.000000 | 10.075000 | RSOph | archived | Feb 14 2006 11:50AM | Feb 26 2006 3:36PM | N | Starrfield |
07 | 500693 | 7277 | ACIS-S | NONE | 15.000000 | 14.998400 | SN2005ke | archived | Feb 7 2006 9:31AM | Feb 19 2006 11:11AM | N | Immler |
07 | 500692 | 7276 | HRC-I | NONE | 1.000000 | 1.112125 | IGRJ15359-5750 | archived | Feb 6 2006 12:40PM | Mar 28 2006 4:54AM | N | Israel |
07 | 500691 | 7275 | HRC-I | NONE | 1.000000 | 1.122631 | IGRJ18048-1455 | archived | Feb 6 2006 12:40PM | Mar 28 2006 4:10AM | N | Israel |
07 | 500690 | 7274 | HRC-I | NONE | 1.000000 | 1.097006 | IGRJ17513-2011 | archived | Feb 6 2006 12:40PM | Mar 28 2006 3:40AM | N | Israel |
07 | 500689 | 7273 | HRC-I | NONE | 1.000000 | 1.095981 | IGRJ17488-3253 | archived | Feb 6 2006 12:40PM | Mar 28 2006 3:07AM | N | Israel |
07 | 400559 | 7272 | HRC-I | NONE | 2.000000 | 2.135331 | SWIFTJ1626.6-5156 | archived | Feb 2 2006 3:13PM | Feb 21 2006 6:28AM | N | Homan |
07 | 400558 | 7269 | ACIS-S | NONE | 1.000000 | 1.161600 | HD109962 | archived | Jan 23 2006 1:03PM | Feb 2 2006 2:14PM | N | Walter |
06 | 500685 | 7241 | ACIS-S | NONE | 50.000000 | 50.179190 | SN2005gj | archived | Nov 29 2005 4:53PM | Dec 11 2005 5:26PM | N | Pooley |
05 | 800555 | 7225 | ACIS-I | NONE | 2.000000 | 2.045959 | MACS1720.3+3536 | archived | Nov 9 2005 3:10PM | Nov 27 2005 3:12AM | N | Allen |
06 | 300171 | 7186 | ACIS-S | HETG | 50.000000 | 50.155000 | RTCru | archived | Oct 5 2005 2:19PM | Oct 19 2005 10:41AM | N | Sokoloski |
06 | 200372 | 6375 | HRC-I | NONE | 5.000000 | 5.150881 | AlphaCentauri | archived | Aug 31 2005 11:31AM | Dec 17 2006 4:58AM | N | AYRES |
06 | 200371 | 6374 | HRC-I | NONE | 5.000000 | 5.157031 | AlphaCentauri | archived | Aug 31 2005 11:31AM | May 12 2006 6:31PM | N | AYRES |
06 | 200370 | 6373 | HRC-I | NONE | 5.000000 | 5.187781 | AlphaCentauri | archived | Aug 31 2005 11:31AM | Oct 21 2005 2:59AM | N | AYRES |
06 | 400472 | 6354 | ACIS-S | NONE | 20.000000 | 19.043960 | GRB050709 | archived | Jul 19 2005 11:34AM | Jul 25 2005 9:03PM | N | Frail |
06 | 400470 | 6298 | HRC-I | NONE | 5.000000 | 4.767531 | SAXJ1808.4-3658 | archived | Jun 7 2005 9:38AM | Jun 20 2005 11:25PM | N | Chakrabarty |
06 | 400469 | 6297 | ACIS-S | HETG | 15.000000 | 14.344000 | SAXJ1808.4-3658 | archived | Jun 6 2005 3:27PM | Jun 12 2005 2:32AM | N | Galloway |
06 | 500603 | 6284 | ACIS-S | NONE | 30.000000 | 29.788040 | SN2005bx | archived | May 6 2005 3:24PM | Jul 30 2005 11:11AM | N | Filippenko |
06 | 701180 | 6278 | ACIS-I | NONE | 3.500000 | 3.638000 | IGRJ19473+4452 | archived | Apr 20 2005 2:33PM | Jul 31 2005 9:32AM | N | Sunyaev |
06 | 701179 | 6277 | ACIS-I | NONE | 3.500000 | 3.759572 | IGRJ13091+1137 | archived | Apr 20 2005 2:33PM | Jul 25 2005 10:25AM | N | Sunyaev |
06 | 701178 | 6276 | ACIS-I | NONE | 3.500000 | 3.260449 | IGRJ12391-1612 | archived | Apr 20 2005 2:33PM | Jul 25 2005 11:45AM | N | Sunyaev |
06 | 701177 | 6275 | ACIS-I | NONE | 3.500000 | 3.260799 | IGRJ12026-5349 | archived | Apr 20 2005 2:33PM | Jun 16 2005 6:10AM | N | Sunyaev |
06 | 701176 | 6274 | ACIS-I | NONE | 3.500000 | 3.676799 | IGRJ11085-5100 | archived | Apr 20 2005 2:33PM | Jul 1 2005 3:58AM | N | Sunyaev |
06 | 701175 | 6273 | ACIS-I | NONE | 3.500000 | 3.707715 | IGRJ10252-6829 | archived | Apr 20 2005 2:33PM | Jul 30 2005 9:24AM | N | Sunyaev |
06 | 701174 | 6272 | ACIS-I | NONE | 3.500000 | 3.257599 | IGRJ07563-4137 | archived | Apr 20 2005 2:33PM | Jun 16 2005 4:46AM | N | Sunyaev |
06 | 701173 | 6271 | ACIS-I | NONE | 3.500000 | 3.459199 | IGRJ05007-7047 | archived | Apr 20 2005 2:33PM | Jun 16 2005 3:25AM | N | Sunyaev |
06 | 500601 | 6269 | ACIS-S | NONE | 20.000000 | 20.184090 | GRB050412 | archived | Apr 14 2005 10:32AM | Apr 17 2005 9:43AM | N | Berger |
06 | 400468 | 6261 | ACIS-S | NONE | 10.000000 | 10.180800 | PSRJ1638-4725 | archived | Mar 14 2005 10:52AM | May 4 2005 7:47PM | N | McLaughlin |
05 | 500600 | 6260 | ACIS-S | NONE | 10.000000 | 10.140790 | GCRTJ1745-3009 | archived | Mar 10 2005 3:52PM | May 1 2005 12:47AM | D | Hyman |
06 | 400467 | 6259 | ACIS-S | NONE | 5.000000 | 5.169599 | HESSJ1826-148 | archived | Mar 10 2005 3:26PM | Apr 13 2005 3:01AM | N | Funk |
06 | 500599 | 6251 | HRC-S | NONE | 30.000000 | 27.149430 | SGR1806-20 | archived | Feb 22 2005 3:08PM | Apr 22 2005 7:03PM | D | Kouveliotou |
06 | 701172 | 6227 | ACIS-S | NONE | 10.000000 | 10.323190 | NGC3690 | archived | Feb 8 2005 11:54AM | Feb 14 2005 4:53AM | N | Nandra |
06 | 500598 | 6224 | ACIS-I | NONE | 20.000000 | 19.059190 | SGR1806-20 | archived | Jan 27 2005 5:35PM | Feb 9 2005 7:25AM | 1 | Fox |
06 | 500597 | 6207 | ACIS-S | NONE | 30.000000 | 29.100500 | SGR1806-20 | archived | Jan 18 2005 10:13AM | Feb 8 2005 10:54PM | 1 | Rea |
06 | 200363 | 6204 | ACIS-S | NONE | 5.000000 | 5.136400 | V1118Ori | archived | Jan 18 2005 9:48AM | Jan 26 2005 3:24AM | D | Audard |
06 | 400447 | 6181 | ACIS-S | NONE | 15.000000 | 14.182800 | IGRJ00291+5934 | archived | Dec 17 2004 5:25PM | Feb 6 2005 1:45PM | N | Jonker |
06 | 400446 | 6180 | ACIS-S | NONE | 10.000000 | 9.894359 | IGRJ00291+5934 | archived | Dec 17 2004 5:25PM | Jan 14 2005 12:11AM | N | Jonker |
06 | 400445 | 6179 | ACIS-S | NONE | 5.000000 | 5.185200 | IGRJ00291+5934 | archived | Dec 17 2004 5:25PM | Jan 1 2005 9:24PM | N | Jonker |
05 | 800557 | 6172 | ACIS-I | NONE | 30.000000 | 30.144270 | MACS1621.6+3810 | archived | Nov 30 2004 9:54AM | Dec 25 2004 10:04PM | N | Allen |
05 | 500591 | 6129 | ACIS-I | NONE | 20.000000 | 19.508000 | GRB040912 | archived | Sep 13 2004 1:18PM | Sep 21 2004 11:18AM | N | Ricker |
05 | 500590 | 6128 | ACIS-I | NONE | 20.000000 | 18.168000 | GRB040912 | archived | Sep 13 2004 1:18PM | Sep 15 2004 10:24PM | N | Ricker |
05 | 800560 | 6112 | ACIS-I | NONE | 10.000000 | 9.510799 | MACS1427.2+4407 | archived | Aug 24 2004 2:41PM | Feb 12 2005 2:19AM | N | Allen |
05 | 800559 | 6111 | ACIS-I | NONE | 50.000000 | 50.157877 | MACS0744.9+3927 | archived | Aug 24 2004 2:41PM | Dec 3 2004 9:25PM | N | Allen |
05 | 800558 | 6110 | ACIS-I | NONE | 70.000000 | 64.042810 | MACS1311.0-0311 | archived | Aug 24 2004 2:41PM | Apr 20 2005 12:23AM | N | Allen |
05 | 800557 | 6109 | ACIS-I | NONE | 40.000000 | 38.046250 | MACS1621.6+3810 | archived | Aug 24 2004 2:41PM | Dec 11 2004 2:31PM | N | Allen |
05 | 800556 | 6108 | ACIS-I | NONE | 40.000000 | 40.169750 | MACS0329.7-0212 | archived | Aug 24 2004 2:41PM | Dec 6 2004 6:18AM | N | Allen |
05 | 800555 | 6107 | ACIS-I | NONE | 38.000000 | 34.332410 | MACS1720.3+3536 | archived | Aug 24 2004 2:41PM | Nov 22 2005 9:35PM | N | Allen |
05 | 800554 | 6106 | ACIS-I | NONE | 40.000000 | 35.770890 | MACS0159.8-0849 | archived | Aug 24 2004 2:41PM | Dec 4 2004 12:14PM | N | Allen |
05 | 800553 | 6105 | ACIS-I | NONE | 40.000000 | 37.770350 | MACS0011.7-1523 | archived | Aug 24 2004 2:41PM | Jun 28 2005 11:51AM | N | Allen |
05 | 800552 | 6104 | ACIS-I | NONE | 10.000000 | 9.737000 | Abell2204 | archived | Aug 24 2004 2:41PM | Sep 20 2004 11:42AM | N | Allen |
05 | 800551 | 6103 | ACIS-I | NONE | 10.000000 | 10.406000 | PKS0745-191 | archived | Aug 24 2004 2:41PM | Sep 24 2004 12:35AM | N | Allen |
05 | 800550 | 6102 | ACIS-I | NONE | 10.000000 | 10.127000 | Abell478 | archived | Aug 24 2004 2:41PM | Sep 13 2004 5:15PM | N | Allen |
05 | 800549 | 6101 | ACIS-I | NONE | 10.000000 | 10.050190 | Abell2029 | archived | Aug 24 2004 2:41PM | Dec 17 2004 3:50AM | N | Allen |
05 | 500585 | 6098 | ACIS-I | NONE | 5.000000 | 4.707000 | HESSJ1303-631 | archived | Aug 18 2004 9:57AM | Sep 25 2004 6:02PM | D | Halpern |
05 | 500508 | 5365 | ACIS-S | NONE | 10.000000 | 10.163000 | GRB040812 | archived | Aug 13 2004 12:06PM | Aug 22 2004 10:12AM | N | Kouveliotou |
05 | 500507 | 5364 | ACIS-S | NONE | 10.000000 | 10.175000 | GRB040812 | archived | Aug 13 2004 12:06PM | Aug 17 2004 7:28AM | N | Kouveliotou |
05 | 600412 | 5360 | ACIS-I | NONE | 5.000000 | 5.174000 | CXOGCJ174540.0-2900 | archived | Aug 3 2004 5:00PM | Aug 28 2004 12:21PM | N | Baganoff |
04 | 100052 | 5352 | HRC-I | NONE | 4.700000 | 4.657000 | Moon | archived | Jul 13 2004 3:11PM | Jul 28 2004 1:30AM | N | Drake |
04 | 100052 | 5351 | HRC-I | NONE | 5.600000 | 5.471000 | Moon | archived | Jul 13 2004 3:11PM | Jul 27 2004 11:13PM | N | Drake |
04 | 100052 | 5327 | HRC-I | NONE | 5.600000 | 5.638000 | Moon | archived | May 12 2004 1:59PM | Jun 2 2004 10:58AM | N | Drake |
05 | 100053 | 5326 | ACIS-S | NONE | 3.300000 | 3.471000 | Comet2001Q4(NEAT) | archived | May 3 2004 2:15PM | May 12 2004 8:58PM | D | Lisse |
05 | 100053 | 5325 | ACIS-S | NONE | 3.300000 | 3.484000 | Comet2001Q4(NEAT) | archived | May 3 2004 2:14PM | May 12 2004 7:55PM | D | Lisse |
04 | 100052 | 5324 | HRC-I | NONE | 5.640000 | 5.772000 | Moon | archived | Apr 23 2004 2:22PM | May 4 2004 7:00AM | N | Drake |
05 | 100053 | 5321 | ACIS-S | NONE | 3.400000 | 3.558000 | Comet2001Q4(NEAT) | archived | Apr 16 2004 2:05PM | May 12 2004 6:50PM | D | Lisse |
05 | 500506 | 5314 | ACIS-S | NONE | 30.000000 | 30.156000 | GRB031203 | archived | Mar 17 2004 5:29PM | Apr 18 2004 11:59AM | D | Kouveliotou |
04 | 100052 | 5312 | HRC-I | NONE | 5.600000 | 5.679000 | Moon | archived | Mar 15 2004 2:11PM | Jun 2 2004 8:41AM | N | Drake |
04 | 100052 | 5311 | HRC-I | NONE | 5.640000 | 5.521000 | Moon | archived | Mar 15 2004 2:05PM | May 4 2004 4:36AM | N | Drake |
05 | 200298 | 5308 | ACIS-S | NONE | 5.000000 | 4.963000 | IRAS05436-0007 | archived | Feb 19 2004 6:43PM | Mar 22 2004 12:35AM | N | Kastner |
05 | 200297 | 5307 | ACIS-S | NONE | 5.000000 | 5.561000 | IRAS05436-0007 | archived | Feb 19 2004 6:43PM | Mar 7 2004 1:41AM | N | Kastner |
05 | 500505 | 5306 | ACIS-S | NONE | 15.000000 | 14.758000 | SN2001em | archived | Feb 9 2004 3:39PM | Apr 4 2004 7:41PM | N | Pooley |
05 | 500504 | 5305 | HRC-S | LETG | 35.000000 | 35.705000 | RXJ0720.4-3125 | archived | Feb 9 2004 3:38PM | Feb 27 2004 4:53AM | N | Vink |
05 | 701014 | 5302 | ACIS-S | NONE | 30.000000 | 31.121000 | NGC4395 | archived | Jan 30 2004 8:22AM | Apr 11 2004 1:28AM | N | Moran |
05 | 701013 | 5301 | ACIS-S | NONE | 30.000000 | 29.730000 | NGC4395 | archived | Jan 30 2004 8:22AM | Apr 10 2004 3:06AM | N | Moran |
05 | 500503 | 5298 | ACIS-S | NONE | 25.000000 | 21.848000 | GRB031203 | archived | Jan 13 2004 11:16AM | Jan 22 2004 9:34PM | N | Kulkarni |
05 | 300145 | 5293 | HRC-S | LETG | 40.000000 | 41.953000 | MiraAB | archived | Dec 19 2003 11:52AM | Jan 11 2004 2:09PM | D | Karovska |
05 | 300144 | 5292 | HRC-S | LETG | 10.000000 | 10.308000 | V4743Sgr | archived | Dec 18 2003 5:07PM | Feb 28 2004 1:31AM | N | Starrfield |
05 | 400376 | 5291 | ACIS-S | NONE | 10.000000 | 10.137000 | PSRJ0737-3039 | archived | Dec 18 2003 4:54PM | Jan 18 2004 7:56PM | 1 | McLaughlin |
04 | 500500 | 5247 | HRC-I | NONE | 5.000000 | 4.871000 | IGRJ16316-4028 | archived | Oct 31 2003 1:24PM | Jan 18 2004 1:07PM | D | Foschini |
04 | 500499 | 5246 | ACIS-S | NONE | 25.000000 | 25.509000 | SN2003jd | archived | Oct 31 2003 1:20PM | Nov 10 2003 7:08PM | N | Watson |
04 | 500498 | 5240 | HRC-I | NONE | 3.000000 | 2.884000 | XTEJ1810-197 | archived | Oct 9 2003 2:54PM | Nov 1 2003 3:26PM | N | Israel |
04 | 200237 | 4455 | ACIS-S | NONE | 20.000000 | 19.898000 | EtaCar | archived | Aug 14 2003 12:21PM | Aug 28 2003 5:53PM | S | Corcoran |
04 | 500415 | 4454 | HRC-I | NONE | 3.000000 | 2.833000 | XTEJ1810-197 | archived | Aug 12 2003 2:22PM | Aug 27 2003 10:43PM | N | Gotthelf |
04 | 500413 | 4449 | ACIS-S | NONE | 20.000000 | 18.435000 | SN2002ic | archived | Aug 4 2003 2:52PM | Aug 11 2003 9:40PM | D | Hughes |
04 | 500412 | 4443 | ACIS-S | NONE | 25.000000 | 25.125000 | SGR1806-20 | archived | Jul 21 2003 6:54PM | Aug 3 2003 12:13PM | D | Woods |
04 | 400324 | 4439 | ACIS-S | HETG | 10.000000 | 9.987000 | XTEJ1814-338 | archived | Jun 6 2003 4:18PM | Jun 20 2003 2:12AM | D | Chakrabarty |
04 | 800375 | 4438 | ACIS-S | NONE | 30.000000 | 29.136000 | RCS0439.6-2905 | archived | May 12 2003 2:31PM | Jun 6 2003 6:17AM | D | Bautz |
04 | 400323 | 4434 | ACIS-S | NONE | 47.000000 | 47.051000 | IGRJ16358-4726 | archived | Apr 10 2003 4:23PM | Apr 21 2003 3:49AM | D | Kouveliotou |
04 | 500411 | 4432 | ACIS-S | LETG | 100.000000 | 98.100000 | GRB030328 | archived | Mar 28 2003 10:14AM | Mar 29 2003 3:05AM | N | Ricker |
04 | 400322 | 4426 | HRC-S | NONE | 3.000000 | 2.824000 | XTEJ1807-294 | archived | Feb 27 2003 3:35PM | Mar 10 2003 8:34AM | D | MARKWARDT |
04 | 500410 | 4425 | ACIS-S | NONE | 40.000000 | 40.172000 | GRB030226 | archived | Feb 26 2003 3:15PM | Feb 27 2003 5:14PM | N | Pedersen |
04 | 400321 | 4424 | ACIS-S | NONE | 10.000000 | 10.687000 | XTEJ1908+094 | archived | Feb 20 2003 2:41PM | May 14 2003 1:51AM | D | Jonker |
04 | 400320 | 4423 | ACIS-S | NONE | 5.000000 | 5.150000 | XTEJ1908+094 | archived | Feb 20 2003 2:41PM | Apr 19 2003 3:14PM | D | Jonker |
04 | 400319 | 4422 | ACIS-S | NONE | 5.000000 | 5.212000 | XTEJ1908+094 | archived | Feb 20 2003 2:41PM | Mar 24 2003 12:07AM | D | Jonker |
04 | 400318 | 4420 | ACIS-S | HETG | 75.000000 | 76.220000 | GX339-4 | archived | Feb 12 2003 1:59PM | Mar 17 2003 8:05PM | D | Miller |
04 | 500409 | 4417 | ACIS-S | NONE | 30.000000 | 30.415000 | SN2003L | archived | Jan 30 2003 7:05PM | Feb 10 2003 3:59AM | N | Kulkarni |
03 | 100038 | 4410 | HRC-I | NONE | 1.000000 | 1.120000 | EARTH | archived | Dec 4 2002 4:43PM | Feb 7 2003 1:23AM | D | Gladstone |
03 | 500408 | 4409 | ACIS-S | NONE | 30.000000 | 30.431000 | GRB021004 | archived | Nov 17 2002 12:28PM | Nov 25 2002 5:51PM | N | Sako |
03 | 500407 | 4405 | ACIS-S | NONE | 10.000000 | 10.115000 | SN2002HI | archived | Nov 7 2002 8:46PM | Dec 10 2002 5:45PM | N | Lewin |
03 | 500406 | 4404 | ACIS-S | NONE | 30.000000 | 30.335000 | SN2002HH | archived | Nov 7 2002 8:42PM | Nov 25 2002 8:58AM | N | Lewin |
03 | 500405 | 4381 | ACIS-S | HETG | 80.000000 | 88.130000 | GRB021004 | archived | Oct 4 2002 12:41PM | Oct 5 2002 8:58AM | N | Harrison |
03 | 500404 | 4364 | ACIS-S | HETG | 80.000000 | 78.122000 | GRB020813 | archived | Aug 13 2002 5:56AM | Aug 13 2002 11:46PM | N | Ricker |
03 | 600330 | 4360 | ACIS-I | NONE | 5.000000 | 4.969000 | M31 | archived | Aug 2 2002 9:52AM | Aug 11 2002 6:15PM | N | Primini |
03 | 400316 | 4358 | ACIS-I | NONE | 5.000000 | 4.979000 | TEVJ2032+4130 | archived | Aug 1 2002 5:35PM | Aug 11 2002 8:07PM | D | Butt |
03 | 400315 | 4285 | ACIS-S | NONE | 5.000000 | 4.687000 | V4641SGR | archived | Jul 19 2002 11:42AM | Aug 5 2002 4:16AM | D | Rupen |
03 | 400270 | 3724 | ACIS-S | HETG | 30.000000 | 26.400000 | CYGX-1 | archived | Jul 15 2002 12:33PM | Jul 30 2002 5:42PM | N | Feng |
03 | 400268 | 3672 | ACIS-S | NONE | 20.000000 | 18.255000 | XTEJ1550-564 | archived | May 29 2002 9:42AM | Jun 19 2002 9:17AM | D | Corbel |
03 | 400267 | 3671 | ACIS-S | NONE | 5.000000 | 5.538000 | 1E1740.7-2942 | archived | May 29 2002 9:33AM | Aug 17 2002 1:24PM | D | Heindl |
03 | 400266 | 3670 | ACIS-S | HETG | 10.000000 | 10.140000 | 1E1740.7-2942 | archived | May 29 2002 9:33AM | Jun 13 2002 7:29PM | D | Heindl |
03 | 400265 | 3661 | ACIS-S | LETG | 20.000000 | 17.961000 | XTEJ0929-314 | archived | May 10 2002 3:51PM | May 15 2002 12:43AM | D | Chakrabarty |
03 | 500298 | 3496 | ACIS-S | NONE | 25.000000 | 24.188000 | SN2001IG | archived | Apr 30 2002 12:59PM | Jun 11 2002 6:20AM | N | Schlegel |
03 | 500297 | 3495 | ACIS-S | NONE | 25.000000 | 23.734000 | SN2001IG | archived | Apr 30 2002 12:59PM | May 21 2002 11:53PM | N | Schlegel |
03 | 500296 | 3494 | ACIS-S | NONE | 15.000000 | 14.755000 | XRF020427 | archived | Apr 29 2002 3:42PM | May 14 2002 3:55AM | N | Fox |
03 | 500295 | 3493 | ACIS-S | NONE | 15.000000 | 13.916000 | XRF020427 | archived | Apr 29 2002 3:42PM | May 6 2002 5:46AM | N | Fox |
03 | 400247 | 3492 | ACIS-S | NONE | 5.000000 | 5.231000 | RXJ170930.2-263927 | archived | Apr 22 2002 3:15PM | Apr 23 2002 9:58PM | D | Jonker |
03 | 400256 | 3490 | ACIS-S | NONE | 7.000000 | 7.648000 | AQLX-1 | archived | Apr 5 2002 12:13PM | Sep 3 2002 4:27PM | D | Rutledge |
03 | 400255 | 3489 | ACIS-S | NONE | 7.000000 | 7.858000 | AQLX-1 | archived | Apr 5 2002 12:13PM | Aug 18 2002 8:19AM | D | Rutledge |
03 | 400254 | 3488 | ACIS-S | NONE | 7.000000 | 7.172000 | AQLX-1 | archived | Apr 5 2002 12:13PM | Jul 22 2002 9:01PM | D | Rutledge |
03 | 400253 | 3487 | ACIS-S | NONE | 7.000000 | 6.549000 | AQLX-1 | archived | Apr 5 2002 12:13PM | Jul 5 2002 3:45PM | D | Rutledge |
03 | 400252 | 3486 | ACIS-S | NONE | 7.000000 | 7.151000 | AQLX-1 | archived | Apr 5 2002 12:13PM | Jun 11 2002 3:50AM | D | Rutledge |
03 | 400251 | 3485 | ACIS-S | NONE | 7.000000 | 7.672000 | AQLX-1 | archived | Apr 5 2002 12:13PM | May 20 2002 7:41AM | D | Rutledge |
03 | 400250 | 3484 | ACIS-S | NONE | 7.000000 | 7.160000 | AQLX-1 | archived | Apr 5 2002 12:13PM | May 4 2002 11:04PM | D | Rutledge |
03 | 400249 | 3483 | HRC-S | NONE | 3.000000 | 2.976000 | XTEJ1751-305 | archived | Apr 5 2002 10:44AM | Apr 10 2002 4:31PM | D | MARKWARDT |
03 | 400248 | 3481 | ACIS-S | NONE | 1.000000 | 1.133000 | XTEJ1908+094 | archived | Apr 3 2002 2:33PM | Apr 15 2002 5:39AM | N | Rupen |
03 | 500294 | 3477 | ACIS-S | NONE | 20.000000 | 20.057000 | GRB020321 | archived | Mar 25 2002 11:28AM | Mar 31 2002 2:13AM | N | Fox |
03 | 400246 | 3475 | ACIS-S | NONE | 5.000000 | 5.965000 | RXJ170930.2-263927 | archived | Mar 19 2002 3:24PM | Apr 10 2002 5:49PM | D | Jonker |
03 | 400239 | 3464 | ACIS-S | NONE | 5.000000 | 5.147000 | RXJ170930.2-263927 | archived | Mar 11 2002 9:44AM | Apr 1 2002 12:43AM | D | Jonker |
03 | 400238 | 3463 | ACIS-S | NONE | 8.477000 | 7.468038 | RXJ170930.2-263927 | archived | Mar 11 2002 9:44AM | Mar 18 2002 11:46AM | D | Jonker |
03 | 400237 | 3462 | ACIS-S | NONE | 15.000000 | 14.210000 | RXJ170930.2-263927 | archived | Mar 11 2002 9:44AM | Mar 12 2002 1:52PM | D | Jonker |
03 | 300090 | 3455 | ACIS-S | HETG | 35.000000 | 34.457000 | GKPER | archived | Mar 6 2002 5:15PM | Apr 9 2002 3:06PM | D | Mauche |
03 | 300089 | 3454 | ACIS-S | HETG | 35.000000 | 32.102000 | GKPER | archived | Mar 6 2002 5:15PM | Mar 27 2002 9:49AM | D | Mauche |
03 | 100034 | 3453 | ACIS-S | NONE | 12.000000 | 11.964000 | Comet2002C1 | archived | Mar 6 2002 2:20PM | Apr 15 2002 11:15PM | D | Dennerl |
03 | 500292 | 3449 | ACIS-S | NONE | 3.000000 | 2.662000 | SGR1900+14 | archived | Feb 27 2002 4:34PM | Mar 11 2002 11:03AM | D | Woods |
03 | 400236 | 3448 | ACIS-S | NONE | 30.000000 | 27.457000 | XTEJ1550-564 | archived | Feb 14 2002 12:00PM | Mar 11 2002 3:16PM | D | Corbel |
03 | 100034 | 3447 | ACIS-S | NONE | 12.000000 | 11.718000 | Comet2002C1 | archived | Feb 14 2002 9:25AM | Apr 15 2002 1:52AM | D | Dennerl |
03 | 500291 | 3441 | ACIS-I | NONE | 15.000000 | 14.672000 | XRF011130 | archived | Feb 4 2002 5:21PM | Feb 20 2002 10:18AM | N | Ricker |
03 | 500287 | 3437 | ACIS-I | NONE | 10.000000 | 10.064000 | GRB020127 | archived | Jan 30 2002 1:31PM | Feb 11 2002 11:17AM | N | Fox |
03 | 500286 | 3436 | ACIS-I | NONE | 10.000000 | 9.968000 | GRB020127 | archived | Jan 30 2002 1:31PM | Jan 31 2002 10:37PM | N | Fox |
03 | 300087 | 3434 | ACIS-S | NONE | 5.000000 | 5.629000 | IMNORMAE | archived | Jan 23 2002 12:58PM | Feb 4 2002 6:01PM | N | Starrfield |
03 | 700612 | 3419 | ACIS-S | NONE | 100.000000 | 97.944000 | MGJ0414+0534 | archived | Dec 7 2001 4:55PM | Jan 9 2002 12:00AM | D | Chartas |
03 | 100032 | 3412 | ACIS-S | NONE | 20.000000 | 20.122000 | XRF011030 | archived | Nov 15 2001 3:17PM | Nov 29 2001 11:09AM | D | Harrison |
03 | 100031 | 3411 | ACIS-S | NONE | 50.000000 | 47.209000 | XRF011030 | archived | Nov 9 2001 12:48AM | Nov 9 2001 5:44PM | N | Harrison |
02 | 400234 | 3407 | ACIS-S | HETG | 30.000000 | 30.070000 | CYGX-1 | archived | Oct 19 2001 10:35AM | Oct 28 2001 4:33PM | D | Cui |
02 | 500285 | 3399 | HRC-S | LETG | 9.500000 | 9.318000 | RXJ1856.5-3754 | archived | Oct 1 2001 9:20AM | Oct 15 2001 11:59AM | N | Tananbaum |
02 | 700608 | 3395 | ACIS-S | NONE | 30.000000 | 28.777000 | MGJ0414+0534 | archived | Sep 27 2001 10:49AM | Nov 9 2001 8:34AM | D | Chartas |
02 | 500285 | 3382 | HRC-S | LETG | 100.500000 | 101.926000 | RXJ1856.5-3754 | archived | Sep 18 2001 4:46PM | Oct 8 2001 8:31AM | N | Tananbaum |
02 | 500285 | 3381 | HRC-S | LETG | 170.000000 | 171.073000 | RXJ1856.5-3754 | archived | Sep 18 2001 4:46PM | Oct 12 2001 7:31PM | N | Tananbaum |
02 | 500285 | 3380 | HRC-S | LETG | 170.000000 | 167.446000 | RXJ1856.5-3754 | archived | Sep 18 2001 4:43PM | Oct 10 2001 5:18AM | N | Tananbaum |
02 | 400233 | 3360 | ACIS-S | NONE | 2.500000 | 2.641000 | NGC6440 | archived | Aug 15 2001 12:28PM | Aug 18 2001 8:23PM | N | in'tZand |
02 | 700607 | 3359 | ACIS-S | NONE | 6.000000 | 5.760000 | QSOJ0836+0054 | archived | Aug 10 2001 4:26PM | Jan 29 2002 12:02PM | N | Brandt |
02 | 700606 | 3358 | ACIS-S | NONE | 8.000000 | 8.262000 | QSOJ1306+0356 | archived | Aug 10 2001 4:26PM | Jan 29 2002 6:28AM | N | Brandt |
02 | 700605 | 3357 | ACIS-S | NONE | 8.000000 | 8.057000 | QSOJ1030+0524 | archived | Aug 10 2001 2:46PM | Jan 29 2002 9:11AM | N | Brandt |
02 | 300067 | 2514 | ACIS-S | NONE | 10.000000 | 10.179000 | WZSGE | archived | Jul 31 2001 1:15PM | Sep 19 2001 1:56AM | N | Kuulkers |
02 | 300066 | 2513 | ACIS-S | NONE | 10.000000 | 12.075000 | WZSGE | archived | Jul 31 2001 1:15PM | Aug 22 2001 8:41AM | N | Kuulkers |
02 | 300065 | 2512 | ACIS-S | NONE | 5.000000 | 4.910000 | WZSGE | archived | Jul 31 2001 1:15PM | Aug 7 2001 5:47PM | N | Kuulkers |
02 | 300061 | 2508 | ACIS-S | NONE | 5.000000 | 5.159000 | WZSGE | archived | Jul 24 2001 6:25PM | Jul 29 2001 4:49PM | N | Wheatley |
02 | 300059 | 2506 | HRC-S | LETG | 20.000000 | 19.984000 | WZSGE | archived | Jul 24 2001 6:14PM | Aug 18 2001 8:07AM | N | Wheatley |
02 | 300058 | 2505 | HRC-S | LETG | 20.000000 | 18.760000 | WZSGE | archived | Jul 24 2001 6:14PM | Aug 6 2001 7:53PM | N | Wheatley |
02 | 300057 | 2504 | HRC-S | LETG | 20.000000 | 19.950000 | WZSGE | archived | Jul 24 2001 6:14PM | Jul 27 2001 2:44AM | N | Wheatley |
02 | 300056 | 2492 | ACIS-S | NONE | 20.000000 | 19.885000 | CIAQL | archived | Jul 6 2001 4:17PM | Aug 1 2001 12:52PM | D | Greiner |
02 | 300054 | 2465 | ACIS-S | NONE | 2.000000 | 2.149000 | CIAQL | archived | May 9 2001 12:29PM | Jun 1 2001 8:41PM | D | Greiner |
02 | 500200 | 2459 | ACIS-S | NONE | 20.000000 | 18.896000 | PSRJ1907+0919 | archived | Apr 19 2001 11:22AM | Apr 30 2001 11:27PM | N | Kouveliotou |
02 | 500199 | 2458 | ACIS-S | NONE | 20.000000 | 20.835000 | SGR1900+14 | archived | Apr 18 2001 7:19PM | Apr 22 2001 4:58AM | N | Kulkarni |
02 | 700393 | 2454 | ACIS-S | NONE | 5.000000 | 4.500000 | CIRCINUSGALAXY | archived | Apr 13 2001 1:53PM | May 2 2001 4:20PM | N | Matt |
02 | 400164 | 2430 | HRC-I | NONE | 10.000000 | 9.889000 | GRS1758-258 | archived | Mar 9 2001 12:43PM | Mar 24 2001 7:43AM | D | Heindl |
02 | 400163 | 2429 | ACIS-S | HETG | 30.000000 | 30.320000 | GRS1758-258 | archived | Mar 9 2001 12:43PM | Mar 24 2001 10:58AM | D | Heindl |
02 | 400162 | 2428 | ACIS-S | NONE | 20.000000 | 20.400000 | KS1731-260 | archived | Mar 7 2001 3:25PM | Mar 27 2001 12:34AM | D | Wijnands |
02 | 800178 | 2427 | ACIS-S | NONE | 20.000000 | 18.094000 | PKS0745-191 | archived | Mar 7 2001 10:46AM | Jun 16 2001 5:50AM | D | Fabian |
02 | 500197 | 2424 | ACIS-S | NONE | 30.000000 | 29.923000 | GRB010222 | archived | Feb 22 2001 10:36AM | Feb 22 2001 10:28PM | D | Piro |
02 | 400161 | 2415 | ACIS-S | HETG | 30.000000 | 30.146000 | CYGNUSX-1 | archived | Dec 16 2000 3:51PM | Jan 4 2001 6:20AM | D | Miller |
02 | 900066 | 2409 | ACIS-I | NONE | 69.000000 | 69.895000 | ChandraDeepFieldS | archived | Dec 5 2000 4:47PM | Dec 19 2000 4:12AM | N | GIACCONI |
02 | 900066 | 2406 | ACIS-I | NONE | 31.000000 | 30.079000 | ChandraDeepFieldS | archived | Dec 1 2000 2:25PM | Dec 10 2000 11:51PM | N | GIACCONI |
02 | 200125 | 2338 | ACIS-S | HETG | 25.000000 | 24.838000 | WR140 | archived | Oct 27 2000 10:51AM | May 8 2001 8:01PM | D | Pollock |
02 | 200124 | 2337 | ACIS-S | HETG | 50.000000 | 46.124000 | WR140 | archived | Oct 27 2000 10:51AM | Dec 29 2000 10:32AM | D | Pollock |
01 | 300053 | 2336 | ACIS-S | HETG | 20.000000 | 19.222000 | ZANDROMEDAE | archived | Oct 26 2000 3:36PM | Nov 13 2000 3:19PM | D | Charles |
02 | 900066 | 2313 | ACIS-I | NONE | 132.000000 | 132.115000 | ChandraDeepFieldS | archived | Sep 22 2000 10:04AM | Dec 21 2000 2:28AM | N | GIACCONI |
02 | 900066 | 2312 | ACIS-I | NONE | 136.000000 | 125.323000 | ChandraDeepFieldS | archived | Sep 22 2000 10:04AM | Dec 13 2000 3:47AM | N | GIACCONI |
02 | 900066 | 2239 | ACIS-I | NONE | 132.000000 | 132.469000 | ChandraDeepFieldS | archived | Aug 28 2000 4:08PM | Dec 23 2000 5:49PM | N | GIACCONI |
01 | 400112 | 1846 | ACIS-S | NONE | 5.000000 | 4.630000 | XTEJ1550-564 | archived | Aug 7 2000 3:27PM | Sep 11 2000 5:10AM | D | Tomsick |
01 | 400111 | 1845 | ACIS-S | NONE | 5.000000 | 5.164000 | XTEJ1550-564 | archived | Aug 7 2000 3:27PM | Aug 21 2000 9:08AM | D | Tomsick |
01 | 700266 | 1715 | HRC-S | LETG | 20.000000 | 19.839000 | MRK421 | archived | May 8 2000 5:01PM | May 29 2000 5:53PM | N | Fruscione |
01 | 700265 | 1714 | ACIS-S | HETG | 20.000000 | 19.830000 | MRK421 | archived | May 8 2000 5:01PM | May 29 2000 11:57AM | N | Fruscione |
01 | 300041 | 1706 | ACIS-S | HETG | 60.000000 | 59.881000 | EXHYA | archived | Apr 13 2000 3:23PM | May 18 2000 9:59AM | D | Howell |
01 | 400110 | 1701 | ACIS-S | LETG | 30.000000 | 27.830000 | XTEJ1118+480 | archived | Apr 7 2000 3:32PM | Apr 18 2000 6:36PM | D | McClintock |
01 | 700202 | 442 | ACIS-S | NONE | 5.000000 | 4.976000 | NGC526A | archived | Mar 16 2000 9:26AM | Apr 23 2000 6:54AM | S | Wilson |
01 | 400093 | 426 | ACIS-S | HETG | 20.000000 | 18.318000 | CYGX-3 | archived | Feb 16 2000 2:09PM | Apr 6 2000 8:17PM | N | McCollough |
01 | 400092 | 425 | ACIS-S | HETG | 20.000000 | 21.654000 | CYGX-3 | archived | Feb 16 2000 2:09PM | Apr 4 2000 2:05PM | N | McCollough |
01 | 300037 | 327 | ACIS-S | NONE | 5.000000 | 4.947000 | 2MASSJ06285693+7202 | archived | Jan 20 2000 10:10AM | Feb 8 2000 4:18PM | D | DiStefano |
01 | 500093 | 364 | HRC-I | NONE | 50.000000 | 48.159000 | PSRB0833-45 | archived | Jan 19 2000 11:30AM | Feb 21 2000 2:11AM | N | Helfand |
01 | 300037 | 327 | ACIS-S | NONE | 5.000000 | 4.947000 | 2MASSJ06285693+7202 | archived | Jan 19 2000 11:30AM | Feb 8 2000 4:18PM | D | DiStefano |
01 | 570470 | 1520 | ACIS-S | NONE | 25.000000 | 24.035000 | NGC3184 | archived | Jan 19 2000 11:21AM | Feb 3 2000 11:00AM | 3 | Schlegel |
01 | 100011 | 1465 | HRC-S | LETG | 23.150000 | 23.418000 | JUPITER | archived | Oct 20 1999 1:31PM | Nov 26 1999 8:07PM | 3 | WAITE |
01 | 100011 | 1464 | HRC-S | LETG | 14.760000 | 14.778000 | JUPITER | archived | Oct 20 1999 1:30PM | Nov 26 1999 2:35PM | 3 | WAITE |
01 | 100010 | 1463 | ACIS-S | NONE | 22.600000 | 22.364000 | JUPITER | archived | Oct 20 1999 1:29PM | Nov 26 1999 2:10AM | 3 | WAITE |
Cycle | Sequence Number | ObsID | Instrument | Grating | Approved Exposure Time | Target | Status | PI Name |
---|---|---|---|---|---|---|---|---|
24 | 402520 | 28928 | ACIS-S | NONE | 0.100000 | V404Cyg | canceled | Hynes |
23 | 503447 | 27642 | ACIS-S | NONE | 0.000000 | AT2022tsd | canceled | Ho |
23 | 503446 | 27641 | ACIS-S | NONE | 0.000000 | AT2022tsd | canceled | Ho |
23 | 503445 | 27640 | ACIS-S | NONE | 0.000000 | AT2022tsd | canceled | Ho |
22 | 402291 | 24934 | ACIS-S | HETG | 40.000000 | CenX-4 | canceled | in'tZand |
21 | 704253 | 24647 | ACIS-S | NONE | 30.000000 | ESO253-G003 | canceled | Payne |
21 | 704252 | 24646 | ACIS-S | NONE | 30.000000 | ESO253-G003 | canceled | Payne |
21 | 201346 | 23150 | HRC-I | NONE | 5.000000 | Betelgeuse | canceled | Kashyap |
21 | 201345 | 23149 | HRC-I | NONE | 5.000000 | Betelgeuse | canceled | Kashyap |
20 | 402116 | 22135 | ACIS-S | NONE | 15.000000 | ZTF18abfzgpl | canceled | Ofek |
17 | 201085 | 18820 | ACIS-S | HETG | 30.000000 | Capella | canceled | Petre |
17 | 201085 | 18819 | ACIS-S | HETG | 30.000000 | Capella | canceled | Petre |
15 | 401687 | 17560 | ACIS-S | NONE | 20.000000 | CXOJ122518.6+144545 | canceled | Heida |
13 | 200829 | 14409 | ACIS-S | NONE | 8.000000 | 55Cnc | canceled | Wheatley |
12 | 401296 | 13245 | HRC-I | NONE | 1.000000 | MAXIJ1659-152 | canceled | Jonker |
09 | 900939 | 12311 | ACIS-I | NONE | 18.700000 | ChandraDeepField-S | canceled | Tananbaum |
09 | 900936 | 12214 | ACIS-I | NONE | 40.000000 | ChandraDeepField-S | canceled | Tananbaum |
08 | 900737 | 9577 | ACIS-I | NONE | 30.000000 | ChandraDeepField-S | canceled | Tananbaum |
08 | 900737 | 9576 | ACIS-I | NONE | 2.000000 | ChandraDeepField-S | canceled | Tananbaum |
07 | 200461 | 8475 | ACIS-I | NONE | 10.000000 | L1415EXor | canceled | Kastner |
07 | 300182 | 7301 | ACIS-S | HETG | 15.000000 | RSOph | canceled | Starrfield |
07 | 300181 | 7300 | ACIS-S | HETG | 15.000000 | RSOph | canceled | Starrfield |
07 | 300180 | 7299 | HRC-S | LETG | 20.000000 | RSOph | canceled | Starrfield |
06 | 500684 | 7192 | ACIS-S | NONE | 20.000000 | GRB051022 | canceled | Ricker |
06 | 200365 | 6206 | ACIS-S | NONE | 8.333333 | V1118Ori | canceled | Audard |
06 | 200364 | 6205 | ACIS-S | NONE | 8.333333 | V1118Ori | canceled | Audard |
04 | 100052 | 5328 | HRC-I | NONE | 2.500000 | Moon | canceled | Drake |
04 | 100052 | 5313 | HRC-I | NONE | 4.700000 | Moon | canceled | Drake |
04 | 500414 | 4450 | ACIS-S | NONE | 20.000000 | SN2002ic | canceled | Hughes |
03 | 400269 | 3723 | ACIS-S | NONE | 30.000000 | MACHO-99-BLG-22 | canceled | Reynolds |
03 | 500299 | 3497 | ACIS-S | NONE | 25.000000 | SN2001IG | canceled | Schlegel |
03 | 400245 | 3470 | ACIS-S | NONE | 10.000000 | RXJ170930.2-263927 | canceled | Jonker |
03 | 400244 | 3469 | ACIS-S | NONE | 10.000000 | RXJ170930.2-263927 | canceled | Jonker |
03 | 400243 | 3468 | ACIS-S | NONE | 10.000000 | RXJ170930.2-263927 | canceled | Jonker |
03 | 400242 | 3467 | ACIS-S | NONE | 5.000000 | RXJ170930.2-263927 | canceled | Jonker |
03 | 400241 | 3466 | ACIS-S | NONE | 5.000000 | RXJ170930.2-263927 | canceled | Jonker |
03 | 400240 | 3465 | ACIS-S | NONE | 5.000000 | RXJ170930.2-263927 | canceled | Jonker |
03 | 100033 | 3446 | ACIS-S | NONE | 8.000000 | C/2002C1 | canceled | Dennerl |
03 | 500290 | 3440 | ACIS-S | NONE | 25.000000 | SN2002AP | canceled | Schlegel |
03 | 500289 | 3439 | ACIS-S | NONE | 25.000000 | SN2002AP | canceled | Schlegel |
03 | 500288 | 3438 | ACIS-S | NONE | 25.000000 | SN2002AP | canceled | Schlegel |
03 | 300088 | 3435 | ACIS-S | NONE | 25.000000 | IMNORMAE | canceled | Starrfield |
03 | 700614 | 3421 | ACIS-S | NONE | 30.000000 | MGJ0414+0534 | canceled | Chartas |
03 | 700613 | 3420 | ACIS-S | NONE | 30.000000 | MGJ0414+0534 | canceled | Chartas |
02 | 700611 | 3398 | ACIS-S | NONE | 30.000000 | MGJ0414+0534 | canceled | Chartas |
02 | 700610 | 3397 | ACIS-S | NONE | 30.000000 | MGJ0414+0534 | canceled | Chartas |
02 | 700609 | 3396 | ACIS-S | NONE | 30.000000 | MGJ0414+0534 | canceled | Chartas |
01 | 100027 | 3379 | ACIS-S | NONE | 9.000000 | COMET19P/BORRELLY | canceled | Dennerl |
01 | 100027 | 3378 | ACIS-S | NONE | 9.000000 | COMET19P/BORRELLY | canceled | Dennerl |
01 | 100027 | 3377 | ACIS-S | NONE | 9.000000 | COMET19P/BORRELLY | canceled | Dennerl |
01 | 100027 | 2517 | ACIS-S | NONE | 9.000000 | COMET19P/BORRELLY | canceled | Dennerl |
02 | 300064 | 2511 | ACIS-S | NONE | 10.000000 | WZSGE | canceled | Wheatley |
02 | 300063 | 2510 | ACIS-S | NONE | 10.000000 | WZSGE | canceled | Wheatley |
02 | 300062 | 2509 | ACIS-S | NONE | 10.000000 | WZSGE | canceled | Wheatley |
02 | 300055 | 2466 | ACIS-S | NONE | 2.000000 | CIAQL | canceled | Greiner |
02 | 500202 | 2461 | ACIS-S | NONE | 5.000000 | SGR1900+14 | canceled | Kouveliotou |
02 | 500201 | 2460 | ACIS-S | NONE | 5.000000 | SGR1900+14 | canceled | Kouveliotou |
02 | 500198 | 2457 | ACIS-S | NONE | 20.000000 | SGR1900+14 | canceled | Kulkarni |
01 | 400113 | 1847 | ACIS-S | NONE | 5.000000 | XTEJ1550-564 | canceled | Tomsick |
Title : Observing the birth of a stellar mass black hole in M31
PI: De
Abstract: Stellar mass black holes (BHs) form a corner stone of astrophysics;
yet there remains no observational consensus on how they form. The
majority are believed to form from the collapse of massive stellar
cores that fail to explode as a supernova, and instead implode into a
BH. However, identifying individual disappearing stars at
extragalactic distances remains a daunting task. Using archival data
from the NEOWISE survey, we have identified a faint MIR brightening of
a massive supergiant in the Andromeda galaxy, which subsequently has
faded dramatically in optical and bolometric luminosity. Modeling the
exquisitely rich archival dataset, we identify a failed supernova as
the most likely explanation. Here, we propose Chandra ACIS
observations in support of a once-in-a-lifetime opportunity to study a
failed SN in the nearest Milky Way-like galaxy, that will i)
conclusively establish the birth of a BH and ii) reveal the fallback
energetics and the physics of accretion onto the new-born BH.
Title : High-resolution X-ray spectroscopy of Centaurus A with Chandra, XRISM,
and NuSTAR
PI: Bogensberger
Abstract: XRISM will observe Cen A in the week of July 29, for 160 ks. NuSTAR
will simultaneously observe it for 100 ks. Together, the XRISM/Resolve
and NuSTAR spectra will enable an unprecedented broad-band,
high-resolution investigation into the physical properties in the
nearest AGN. However, neither instrument is sensitive to soft X-rays,
and both have a low angular resolution, which causes the spectra to be
contaminated by the jet, X-ray binaries, and diffuse emission from the
galaxy. Both of these issues can be resolved by Chandra, and only by
Chandra. We seek 22 ks of Chandra/HETG spectroscopy taken within two
weeks of the simultaneous XRISM and NuSTAR observations, to accurately
measure the absorption, and determine the degree of contamination of
the AGN spectrum by non-nuclear sources. This will be essential for
determining the spectral continuum even to much higher energies, which
will also be vital for determining key spectral parameters in the
deeper XRISM and NuSTAR observations.
Title : EP240414A, an Einstein Probe fast X-ray transient bridging Luminous
Fast Blue Optical Transients and Long Gam
PI: Jonker
Abstract: The origin of extra-galactic Fast X-ray Transients has remained a
mystery for much of the past 15 years since their first serendipitous
discovery in Chandra observations. Einstein Probe is revolutionizing
the field with many more new discoveries of FXTs than anticipated, and
of FXTs with unique properties. Recently, a new FXT, EP240414a,
without a gamma-ray burst was discovered. An optical counterpart was
quickly found and a redshift of z=0.4 was determined. Interestingly,
the light curve evolution is unlike that of a GRB in either the
optical or the X-ray. The properties of EP240414a seem to be an
amalgamation between some of those of long GRBs and that of a luminous
fast blue optical transient (LFBOT). However, a crucial piece of the
puzzle, the late-time X-ray evolution is currently still missing.
Title : Detecting the X-ray Emission of the Black Hole Gaia BH3
PI: Pacucci
Abstract: A massive black hole (BH) of ~33 solar was recently discovered in a
binary system observed via Gaia's astrometry.
The system is at a distance of ~590 pc, and the orbital period of the
binary is ~11.6 years. This source was never observed in the X-rays.
Contrary to previous discoveries of dormant'' BHs by Gaia (e.g., Gaia
BH1), this BH may be detectable in the X-rays because 1) its mass is
significantly higher; 2) its companion is a giant star with
significantly larger stellar winds; 3) its relatively low distance,
similar to Gaia BH1.
We request 50 ks of Chandra DDT time to detect the X-ray emission from
Gaia BH3 caused by accretion from ISM and/or from the companion's
stellar winds, which we estimate at ~10^-14 erg/s/cm^2.
This source would be the first X-ray detected massive galactic BH. It
would unlock a monitoring campaign of its variability with
Chandra/XMM/Swift, and allow the study of a BH accreting in a
radiatively inefficient mode, which is a physics-rich topic.
Title : Observing the Circumstellar Interaction of the 7 Mpc SN2024ggi
PI: Zimmerman
Abstract: The most common type of Supernovae (SNe) in the universe are Type II
SNe. However, SNe II with detected X-rays are scarce because they are
not bright X-ray emitters. Therefore only extremely nearby SNe are
bright enough to produce detailed X-ray lightcurves and spectra. Such
a SNe has very recently exploded in a very (7 Mpc) nearby galaxy -
SN2024ggi. We propose to obtain Chandea X-ray observations, measuring
the extended wind surrounding the progenitor star. These data will be
unique and are guaranteed to create significant scientific impact. See
attached science justification.
Title : Observing the Circumstellar Interaction of the 7 Mpc SN2024ggi
PI: Zimmerman
Abstract: The most common type of Supernovae (SNe) in the universe are Type II
SNe. However, SNe II with detected X-rays are scarce because they are
not bright X-ray emitters. Therefore only extremely nearby SNe are
bright enough to produce detailed X-ray lightcurves and spectra. Such
a SNe has very recently exploded in a very (7 Mpc) nearby galaxy -
SN2024ggi. We propose to obtain Chandea X-ray observations, measuring
the extended wind surrounding the progenitor star. These data will be
unique and are guaranteed to create significant scientific impact. See
attached science justification.
Title : High energy gratings spectroscopy of novae
PI: Sokolovsky
Abstract: (This is re-submission of the previously discussed DDT request
25308970 from 2024 March 15. The current Swift/XRT count rate for
V1723 Sco is 0.26 cts/s total and 0.088 cts/s in 0.3-2 keV range.) The
peculiar elemental abundances of nova ejecta reveal the composition of
the white dwarf hosting the eruption. Accurate abundances are crucial
for estimating the ejected mass from X-ray absorption. We propose a
30ks Chandra/HETG observation of V1723 Sco that unexpectedly reached
an exceptionally high level of shock-powered X-ray emission (0.3
Swift/XRT cts/s) on 2024-03-13, 33 days after the start of the
eruption. Being only the second classical nova (after V959 Mon)
observed to reach this brightness, V1723 Sco presents a unique
opportunity to perform grating spectroscopy of shocked nova ejecta and
address key questions about nova eruptions in general.
Title : Precise localization of a peculiar fast X-ray transient
PI: Troja
Abstract: LXT240402A is a long duration X-ray transient possibly associated with
a gamma-ray burst GRB240402B. Its position lies close to a nearby
(z~0.045) galaxy, which has been suggested as the possible host
galaxy. The long duration, large offset and nearby distance are
reminiscent of the peculiar GRB230307A and GRB211211A, two nearby long
GRBs produced by the merger of two compact objects. Here we propose a
Chandra observation to cement the association between the X-ray
transient and its optical counterpart. The current error radius of 10
arcsec is not sufficient to rule out a chance alignment, only Chandra
subarcsec accuracy would allow us to robustly link the X-ray and
optical/nIR source, and identify this event as a peculiar transient in
the local universe.
Title : Follow-up Observation of a Peculiar Long-term Soft X-ray Flare
Detected by the EP Mission
PI: Jin
Abstract: Einstein Probe (EP) is a recently launched X-ray mission with 3600
deg^2 lobster-eye FoV, aiming to discover new transients in 0.5-4 keV.
On March 11th 2024, EP detected a bright soft X-ray flare, namely
EP240222a, which was then found to have brightened for two months.
Preliminary multi-wavelength data analyses show that it is likely a
newly born off-center X-ray TDE, and probably involving an IMBH.
Additionally, EP240222a shows peculiar strong X-ray short-term
variability and tentative evidence of outflow absorption features,
both are rarely seen in TDEs. Thus EP240222a has a high scientific
importance for deeper exploration. Here we request a Chandra DDT
observation to quickly follow this newly discovered peculiar
transient. This observation is crucial for spatially confirming its
counterpart, as well as exploring its rare short-term variability and
outflows.
Title : Confirming the X-ray counterpart to ZTF19acnskyy
PI: Hernandez-Garcia
Abstract: The early type galaxy SDSS1335+0728, which had exhibited no prior
optical variations during the previous two decades, began showing
significant nuclear variability in the Zwicky Transient Facility (ZTF)
alert stream in December 2019 (as ZTF19acnskyy). In February 2024,
more than four years after the first optical alert, the source started
showing X-ray emission. However at a distance of 6'' from ZTF19acnskyy
and with a position error of 3.6'', we cannot confirm that it is
related to the optical transient. We request Chandra data to resolve
the position of the X-ray source. If nuclear, we are probably
witnessing the turning-on of an active galactic nucleus (AGN) or an
exotic supermassive black hole transient; if off-nuclear, this could
be a wandering intermediate mass black hole or a very exotic
transient. If we confirm its AGN nature, it could represent the first
observations of an AGN while it is activating.
Title : EP 240315A, the first counterpart to an Einstein Probe fast X-ray
transient
PI: Levan
Abstract: The first optical counterpart and first redshift measurement (z =
4.859) of an X-ray transient discovered by the Einstein Probe have
just been made. We propose a set of 4 urgent Chandra observations in
order to sample the light curve and spectral energy distribution of
this yet unknown transient. Is there a panchromatic afterglow powered
by
synchrotron emission as in GRBs? How does this afterglow decay? Is
there any evidence of late-time engine activity? If there is a
GRB-like decay, and if so, when does it steepen to show signs of any
jet-break which provides an opening angle and total energetics?
Title : EP 240315A, the first counterpart to an Einstein Probe fast X-ray
transient
PI: Levan
Abstract: The first optical counterpart and first redshift measurement (z =
4.859) of an X-ray transient discovered by the Einstein Probe have
just been made. We propose a set of 4 urgent Chandra observations in
order to sample the light curve and spectral energy distribution of
this yet unknown transient. Is there a panchromatic afterglow powered
by
synchrotron emission as in GRBs? How does this afterglow decay? Is
there any evidence of late-time engine activity? If there is a
GRB-like decay, and if so, when does it steepen to show signs of any
jet-break which provides an opening angle and total energetics?
Title : Coordinated CXO/JWST observations of A0620-00
PI: Gallo
Abstract: Our team has upcoming Cycle 2 JWST observations of the quiescent black
hole X-ray binary (BHXB) A0620-00, which is accreting at nearly one
billionth of its Eddington luminosity. We are securing coordinated
(albeit not strictly simultaneous) coverage at virtually all other
wavelengths, yielding the highest-quality spectral energy distribution
of a BHXB ever assembled. This will enable us, for the first time, to
measure the integrated jet power, and confirm or disprove whether
quiescent BHXBs are indeed jet-dominated.
Title : Coordinated CXO/JWST observations of A0620-00
PI: Gallo
Abstract: Our team has upcoming Cycle 2 JWST observations of the quiescent black
hole X-ray binary (BHXB) A0620-00, which is accreting at nearly one
billionth of its Eddington luminosity. We are securing coordinated
(albeit not strictly simultaneous) coverage at virtually all other
wavelengths, yielding the highest-quality spectral energy distribution
of a BHXB ever assembled. This will enable us, for the first time, to
measure the integrated jet power, and confirm or disprove whether
quiescent BHXBs are indeed jet-dominated.
Title : Arcsec localization of the new X-ray transient SRGA J144459.2-604207
PI: Illiano
Abstract: SRGA J144459.2-604207 is a bright and new accreting millisecond pulsar
discovered in outburst on 2024 February 21 (ATel #16464). The best
source position has been so far determined using Swift/XRT at
RA=221.248375 DEC=-60.697972, with an associated uncertainty of 3.5
arcseconds (90% c.l; ATel #16471). These coordinates are however not
fully reliable, given the very high count-rate of the source (i.e.,
about 43 cts/s) and the subsequent pile-up impact. The ongoing efforts
to obtain multi-wavelength counterparts of the source have been so far
not conclusive. At least five optical sources have been reported
within the Swift/XRT position (ATel #16489). In addition, a radio
observation with ATCA has discovered a new bright radio source located
at an offset of 5.5 arcsec with respect to the current X-rays
coordinates. Improved and more accurate localization of the source is
fundamental to identify the multi-band counterpart(s) of the source
and to guide the upcoming observing campaigns.
Title : GRB 240218A
PI: Pena
Abstract: Long duration Gamma-ray Bursts (GRBs) are extremely luminous objects
that can be seen across the universe. At z = 6.78, GRB 240218A has
already been detected in X-ray, optical, and radio wavelengths and
provides a rare opportunity to probe the early universe, tracing star
formation and potentially discovering the first generation of stars!
Multi wavelength observations of GRBs are critical to constraining the
kinetic energy and the progenitor environment. In particular, late
time X-ray observations are essential for deriving the true energetics
of an ultra-relativistic jet. We propose Chandra observations of GRB
240218A to get tighter constraints on the jet break time to determine
the true burst energetics.
Title : Simultaneous observations of HR 1099 with Chandra and XRISM
PI: Miller
Abstract: We request a 30-ksec Chandra ACIS-S/HETG observation of HR 1099 to
overlap with any portion of a 200-ksec XRISM observation planned for
6-10 March 2024 primarily to calibrate the Resolve gain scale at
intermediate energies (2-3 keV).
Title : Simultaneous observations of HR 1099 with Chandra and XRISM
PI: Miller
Abstract: We request a 30-ksec Chandra ACIS-S/HETG observation of HR 1099 to
overlap with any portion of a 200-ksec XRISM observation planned for
6-10 March 2024 primarily to calibrate the Resolve gain scale at
intermediate energies (2-3 keV).
Title : Simultaneous observations of HR 1099 with Chandra and XRISM
PI: Miller
Abstract: We request a 30-ksec Chandra ACIS-S/HETG observation of HR 1099 to
overlap with any portion of a 200-ksec XRISM observation planned for
6-10 March 2024 primarily to calibrate the Resolve gain scale at
intermediate energies (2-3 keV).
Title : Simultaneous Chandra and XRISM Spectroscopy of NGC 4151
PI: Miller
Abstract: XRISM is currently scheduled to observe NGC 4151 on Dec 27, 2023, for
45 ks. This is the first of four planned XRISM exposures; the rest
will likely be taken in late April 2024. Below 4 keV, the HETGS
offers superior resolution to the Resolve calorimeter. Simultaneous -
or at least contemporaneous observations - will provide the best
opportunity to study the variable absorption and winds in NGC 4151,
the nature and origin of the narrow Fe K line, and to search for
relativistic disk reflection. NuSTAR will also observe NGC 4151
providing coverage of the ionizing continuum out to 79 keV, but no
coverage below 3 keV. Chandra spectroscopy is essential for
characterizing the lines and absorption edges at low energy that
ultimately shape the continuum through the Fe K band, where the
strongest outflows and relativistic disk reflection are evident.
[Submitted on behalf of the XRISM team; additional communication with
the Director includes some privileged information.]
Title : Simultaneous Chandra and XRISM Spectroscopy of NGC 4151
PI: Miller
Abstract: XRISM is currently scheduled to observe NGC 4151 on Dec 27, 2023, for
45 ks. This is the first of four planned XRISM exposures; the rest
will likely be taken in late April 2024. Below 4 keV, the HETGS
offers superior resolution to the Resolve calorimeter. Simultaneous -
or at least contemporaneous observations - will provide the best
opportunity to study the variable absorption and winds in NGC 4151,
the nature and origin of the narrow Fe K line, and to search for
relativistic disk reflection. NuSTAR will also observe NGC 4151
providing coverage of the ionizing continuum out to 79 keV, but no
coverage below 3 keV. Chandra spectroscopy is essential for
characterizing the lines and absorption edges at low energy that
ultimately shape the continuum through the Fe K band, where the
strongest outflows and relativistic disk reflection are evident.
[Submitted on behalf of the XRISM team; additional communication with
the Director includes some privileged information.]
Title : Simultaneous Chandra and XRISM Spectroscopy of NGC 4151
PI: Miller
Abstract: XRISM is currently scheduled to observe NGC 4151 on Dec 27, 2023, for
45 ks. This is the first of four planned XRISM exposures; the rest
will likely be taken in late April 2024. Below 4 keV, the HETGS
offers superior resolution to the Resolve calorimeter. Simultaneous -
or at least contemporaneous observations - will provide the best
opportunity to study the variable absorption and winds in NGC 4151,
the nature and origin of the narrow Fe K line, and to search for
relativistic disk reflection. NuSTAR will also observe NGC 4151
providing coverage of the ionizing continuum out to 79 keV, but no
coverage below 3 keV. Chandra spectroscopy is essential for
characterizing the lines and absorption edges at low energy that
ultimately shape the continuum through the Fe K band, where the
strongest outflows and relativistic disk reflection are evident.
[Submitted on behalf of the XRISM team; additional communication with
the Director includes some privileged information.]
Title : TRACKING THE ULX POPULATION ACTIVITY IN NGC 1068 DURING THE IXPE
OBSERVATION
PI: Marinucci
Abstract: We propose two observations of the nuclear region of NGC 1068, 10 ks
each, during the IXPE (Imaging X-ray Polarimeter Explorer) pointing of
the source, in January 2024. We aim at monitoring the flux levels of
the Ultra Luminous X-ray sources (ULXs) within the Field of View of
NGC 1068, which might potentially contaminate the measurement of the
polarization signal from the Active
Galactic Nucleus (AGN). With its superior angular resolution, Chandra
is the only X-ray observatory on orbit which will allow us to
disentangle the emission of the ULXs from the one of the AGN. Since
these contaminating sources vary on timescales of weeks, we require an
ACIS-S observation at the beginning and
another one at the end of the IXPE pointing (03-29 January 2024).
Title : TRACKING THE ULX POPULATION ACTIVITY IN NGC 1068 DURING THE IXPE
OBSERVATION
PI: Marinucci
Abstract: We propose two observations of the nuclear region of NGC 1068, 10 ks
each, during the IXPE (Imaging X-ray Polarimeter Explorer) pointing of
the source, in January 2024. We aim at monitoring the flux levels of
the Ultra Luminous X-ray sources (ULXs) within the Field of View of
NGC 1068, which might potentially contaminate the measurement of the
polarization signal from the Active
Galactic Nucleus (AGN). With its superior angular resolution, Chandra
is the only X-ray observatory on orbit which will allow us to
disentangle the emission of the ULXs from the one of the AGN. Since
these contaminating sources vary on timescales of weeks, we require an
ACIS-S observation at the beginning and
another one at the end of the IXPE pointing (03-29 January 2024).
Title : Microlensing in HE0230-2130
PI: Pooley
Abstract: Image A of the quadruply lensed quasar HE 0230-2130 has experienced a
sudden brightening due to microlensing: 0.4 magnitudes in past 60
days. Such events are uncommon, and multi-wavelength observations of
the rise and peak can set strong constraints on the size of the
emission regions in the quasar since microlensing is sensitive to the
size of the source. If this brightening is due to an eventual caustic
crossing, such a high-magnification event could resolve the central
structure of the quasar on nano-arcsecond scales. We will continue to
monitory the source nightly for at least the next month to follow its
optical evolution. We propose four Chandra observations over the same
period to follow its X-ray evolution. The X-rays are expected to
evolve faster to peak higher than the optical. The sub-arcsecond
separation of images A and B require Chandra's resolution. This is a
rare opportunity that should not be missed.
Title : Chandra/IXPE DDT Observations of Cygnus X-3
PI: McCollough
Abstract: Cygnus X-3 (Cyg X-3) is a well-known microquasar which has a rich
X-ray line spectrum. The X-ray polarization mission IXPE is planning
to make new observations of Cyg X-3 in the latter half the month of
November 2023. Previous IXPE observations have shown Cyg X-3 to be a
highly polarized source in the X-ray (~20%). The polarization
variations as function of energy show a sudden drop in polarization in
the Fe line region (6-7 keV). In this proposal we seek to make
Chandra HETG spectra during the new IXPE observations. We will do a
detailed comparison of Chandra and the polarization of the IXPE
spectra. We will also seek to compare and do an orbital phase analysis
of both spectra and polarization.
Title : Microlensing in HE0230-2130
PI: Pooley
Abstract: Image A of the quadruply lensed quasar HE 0230-2130 has experienced a
sudden brightening due to microlensing: 0.4 magnitudes in past 60
days. Such events are uncommon, and multi-wavelength observations of
the rise and peak can set strong constraints on the size of the
emission regions in the quasar since microlensing is sensitive to the
size of the source. If this brightening is due to an eventual caustic
crossing, such a high-magnification event could resolve the central
structure of the quasar on nano-arcsecond scales. We will continue to
monitory the source nightly for at least the next month to follow its
optical evolution. We propose four Chandra observations over the same
period to follow its X-ray evolution. The X-rays are expected to
evolve faster to peak higher than the optical. The sub-arcsecond
separation of images A and B require Chandra's resolution. This is a
rare opportunity that should not be missed.
Title : Microlensing in HE0230-2130
PI: Pooley
Abstract: Image A of the quadruply lensed quasar HE 0230-2130 has experienced a
sudden brightening due to microlensing: 0.4 magnitudes in past 60
days. Such events are uncommon, and multi-wavelength observations of
the rise and peak can set strong constraints on the size of the
emission regions in the quasar since microlensing is sensitive to the
size of the source. If this brightening is due to an eventual caustic
crossing, such a high-magnification event could resolve the central
structure of the quasar on nano-arcsecond scales. We will continue to
monitory the source nightly for at least the next month to follow its
optical evolution. We propose four Chandra observations over the same
period to follow its X-ray evolution. The X-rays are expected to
evolve faster to peak higher than the optical. The sub-arcsecond
separation of images A and B require Chandra's resolution. This is a
rare opportunity that should not be missed.
Title : Microlensing in HE0230-2130
PI: Pooley
Abstract: Image A of the quadruply lensed quasar HE 0230-2130 has experienced a
sudden brightening due to microlensing: 0.4 magnitudes in past 60
days. Such events are uncommon, and multi-wavelength observations of
the rise and peak can set strong constraints on the size of the
emission regions in the quasar since microlensing is sensitive to the
size of the source. If this brightening is due to an eventual caustic
crossing, such a high-magnification event could resolve the central
structure of the quasar on nano-arcsecond scales. We will continue to
monitory the source nightly for at least the next month to follow its
optical evolution. We propose four Chandra observations over the same
period to follow its X-ray evolution. The X-rays are expected to
evolve faster to peak higher than the optical. The sub-arcsecond
separation of images A and B require Chandra's resolution. This is a
rare opportunity that should not be missed.
Title : Microlensing in HE0230-2130
PI: Pooley
Abstract: Image A of the quadruply lensed quasar HE 0230-2130 has experienced a
sudden brightening due to microlensing: 0.4 magnitudes in past 60
days. Such events are uncommon, and multi-wavelength observations of
the rise and peak can set strong constraints on the size of the
emission regions in the quasar since microlensing is sensitive to the
size of the source. If this brightening is due to an eventual caustic
crossing, such a high-magnification event could resolve the central
structure of the quasar on nano-arcsecond scales. We will continue to
monitory the source nightly for at least the next month to follow its
optical evolution. We propose four Chandra observations over the same
period to follow its X-ray evolution. The X-rays are expected to
evolve faster to peak higher than the optical. The sub-arcsecond
separation of images A and B require Chandra's resolution. This is a
rare opportunity that should not be missed.
Title : Unveiling the nature of a candidate multi-messenger supernova
PI: Stein
Abstract: High energy neutrinos were first discovered in 2013, but their origin
remains largely unknown. Supernovae have long been predicted to
produce high-energy neutrinos through CSM interaction, but there has
thus far been no observational evidence to support these theories.
However, in October 2023, optical follow-up of a neutrino revealed the
first candidate neutrino-SN association. AT2023uqf, a young
rapidly-evolving transient discovered during neutrino follow-up,
resembles an SN Ibn spectroscopically but the lightcurve resembles a
luminous fast blue optical transient. Spectroscopy confirms the
presence of CSM interaction, as required for neutrino production, and
a chance coincidence is disfavoured at 3 sigma significance.
Associations at this level are highly impactful in the field of
neutrino astronomy. We request Chandra observations to test for
LFBOT-like X-ray emission, which could confirm the presence of a
relativistic jet, and would be essential to inform neutrino emission
models.
Title : Unveiling the nature of a candidate multi-messenger supernova
PI: Stein
Abstract: High energy neutrinos were first discovered in 2013, but their origin
remains largely unknown. Supernovae have long been predicted to
produce high-energy neutrinos through CSM interaction, but there has
thus far been no observational evidence to support these theories.
However, in October 2023, optical follow-up of a neutrino revealed the
first candidate neutrino-SN association. AT2023uqf, a young
rapidly-evolving transient discovered during neutrino follow-up,
resembles an SN Ibn spectroscopically but the lightcurve resembles a
luminous fast blue optical transient. Spectroscopy confirms the
presence of CSM interaction, as required for neutrino production, and
a chance coincidence is disfavoured at 3 sigma significance.
Associations at this level are highly impactful in the field of
neutrino astronomy. We request Chandra observations to test for
LFBOT-like X-ray emission, which could confirm the presence of a
relativistic jet, and would be essential to inform neutrino emission
models.
Title : Chandra, JWST, and ALMA Observations of the Quiescent Black Hole
Binary V404 Cyg
PI: Hynes
Abstract: The quiescent black hole X-ray binary V404 Cyg will be observed with
JWST and ALMA. We propose to supplement these observations with
Chandra coverage. V404 Cyg exhibits an IR excess in Spitzer
observations above that expected from either the secondary star or the
accretion disk and proposed to originate from either a relativistic
jet or a circumbinary disk. The JWST-ALMA program is focused on
discriminating these possibilities as ALMA emission should come from
the jet only. Adding Chandra coverage would add information about the
accretion flow near the black hole. The joint Chandra-JWST-ALMA
observations would then probe the inflow-outflow connection and jet
formation close to the black hole at extremely low accretion rates,
and would be compared to predicted multiwavelength lightcurves from
models of internal shocks in jets. These observations when compared to
those from V404 Cyg in outburst would allow a study of jets spanning
five orders of magnitude dynamic range in luminosity.
Title : Observing GRB 230812B - To understand Jet Physics for an Extremely
Bright GRB
PI: Pathak
Abstract: A complete understanding of the physics of GRB jets requires extended
broadband followup observations for detailed source modelling. In
typical GRBs, such inferences are hindered by limited observations,
usually obtained only in the early relatively bright phase of the
afterglow. The very bright GRB 230812B gives a unique opportunity to
obtain high-quality observations extending into late times, where
models remain poorly constrained. It is the brightest GRB for which
hard X-ray polarisation measurements are possible - which can be
completed only if parameters of the jet are inferred from afterglow
data. Chandra is the only instrument that can obtain late-time soft
X-ray data required. The goals of the proposal are to a) to measure
flux and spectroscopic properties of the afterglow at late times, (b)
to identify or constrain the existence of a jet break, and (c) to
leverage the high angular resolution of Chandra to quantify any
possible host galaxy contributions to the X-ray emission.
Title : Observing GRB 230812B - To understand Jet Physics for an Extremely
Bright GRB
PI: Pathak
Abstract: A complete understanding of the physics of GRB jets requires extended
broadband followup observations for detailed source modelling. In
typical GRBs, such inferences are hindered by limited observations,
usually obtained only in the early relatively bright phase of the
afterglow. The very bright GRB 230812B gives a unique opportunity to
obtain high-quality observations extending into late times, where
models remain poorly constrained. It is the brightest GRB for which
hard X-ray polarisation measurements are possible - which can be
completed only if parameters of the jet are inferred from afterglow
data. Chandra is the only instrument that can obtain late-time soft
X-ray data required. The goals of the proposal are to a) to measure
flux and spectroscopic properties of the afterglow at late times, (b)
to identify or constrain the existence of a jet break, and (c) to
leverage the high angular resolution of Chandra to quantify any
possible host galaxy contributions to the X-ray emission.
Title : Observing GRB 230812B - To understand Jet Physics for an Extremely
Bright GRB
PI: Pathak
Abstract: A complete understanding of the physics of GRB jets requires extended
broadband followup observations for detailed source modelling. In
typical GRBs, such inferences are hindered by limited observations,
usually obtained only in the early relatively bright phase of the
afterglow. The very bright GRB 230812B gives a unique opportunity to
obtain high-quality observations extending into late times, where
models remain poorly constrained. It is the brightest GRB for which
hard X-ray polarisation measurements are possible - which can be
completed only if parameters of the jet are inferred from afterglow
data. Chandra is the only instrument that can obtain late-time soft
X-ray data required. The goals of the proposal are to a) to measure
flux and spectroscopic properties of the afterglow at late times, (b)
to identify or constrain the existence of a jet break, and (c) to
leverage the high angular resolution of Chandra to quantify any
possible host galaxy contributions to the X-ray emission.
Title : SN 2023ixf: A bright supernova in M101
PI: Chandra
Abstract: Supernova SN 2023ixf has exploded in a nearby galaxy M101 (d=6.4 Mpc),
discovered on 19 May at a magnitude 14.9. It is one of the closest
supernovae found in the past several decades. The optical spectra has
shown flash ionization features indicating of dense circumstellar
medium (CSM), which powers X-ray and radio emission in a supernova.
Thus we are nearly guaranteed to detect X-ray emission, which can
constrain shock energetics and CSM characteristics. As the supernova
is very young, it is expected to evolve fast. Thats why we request for
two epochs. This will provide understanding of circumstellar
interaction evolution with time, which is crucial since they are
connected to the stellar mass-loss at prior to the supernova. We are
also triggering our approved GMRT radio observations and requested for
for VLA DDT time in 2-25 GHz. Swift-XRT observations are approved for
this supernova. However, Chandra is superior to Swif
to provide accurate determination of column density.
Title : TRACKING THE NE X ACCRETION DISK LINE EMISSION OF ULTRACOMPACT X-RAY
BINARY 4U 1626-67 ACROSS A TORQUE REVERSAL
PI: Ng
Abstract: We propose a 60 ks HETGS observation of the ultracompact X-ray binary
4U 1626-67 that will, for the first time, characterize the Ne X
accretion disk line emission so close in time to a torque reversal. 4U
1626-67 is an unusual ultracompact X-ray binary that hosts a highly
magnetized (B ~ 3x10^(12) G) slowly rotating pulsar (P ~ 7.7 s) and a
low-mass companion (M_c ~ 0.02x solar mass). It is one of the two low
mass X-ray binaries that has exhibited long-term torque reversals (the
other being GX 1+4). Since its discovery in the 1970s, it has
exhibited three torque reversals. The pulse profiles have very
different morphologies between the two spin states, suggesting
significant changes in the accretion geometry. Our proposed
observation will be the closest to a torque reversal of 4U 1626-67,
which will provide us the unique opportunity to track the evolution of
the Ne X line emission across a torque reversal episode and trace the
inner disk location.
Title : TRACKING THE NE X ACCRETION DISK LINE EMISSION OF ULTRACOMPACT X-RAY
BINARY 4U 1626-67 ACROSS A TORQUE REVERSAL
PI: Ng
Abstract: We propose a 60 ks HETGS observation of the ultracompact X-ray binary
4U 1626-67 that will, for the first time, characterize the Ne X
accretion disk line emission so close in time to a torque reversal. 4U
1626-67 is an unusual ultracompact X-ray binary that hosts a highly
magnetized (B ~ 3x10^(12) G) slowly rotating pulsar (P ~ 7.7 s) and a
low-mass companion (M_c ~ 0.02x solar mass). It is one of the two low
mass X-ray binaries that has exhibited long-term torque reversals (the
other being GX 1+4). Since its discovery in the 1970s, it has
exhibited three torque reversals. The pulse profiles have very
different morphologies between the two spin states, suggesting
significant changes in the accretion geometry. Our proposed
observation will be the closest to a torque reversal of 4U 1626-67,
which will provide us the unique opportunity to track the evolution of
the Ne X line emission across a torque reversal episode and trace the
inner disk location.
Title : TRACKING THE NE X ACCRETION DISK LINE EMISSION OF ULTRACOMPACT X-RAY
BINARY 4U 1626-67 ACROSS A TORQUE REVERSAL
PI: Ng
Abstract: We propose a 60 ks HETGS observation of the ultracompact X-ray binary
4U 1626-67 that will, for the first time, characterize the Ne X
accretion disk line emission so close in time to a torque reversal. 4U
1626-67 is an unusual ultracompact X-ray binary that hosts a highly
magnetized (B ~ 3x10^(12) G) slowly rotating pulsar (P ~ 7.7 s) and a
low-mass companion (M_c ~ 0.02x solar mass). It is one of the two low
mass X-ray binaries that has exhibited long-term torque reversals (the
other being GX 1+4). Since its discovery in the 1970s, it has
exhibited three torque reversals. The pulse profiles have very
different morphologies between the two spin states, suggesting
significant changes in the accretion geometry. Our proposed
observation will be the closest to a torque reversal of 4U 1626-67,
which will provide us the unique opportunity to track the evolution of
the Ne X line emission across a torque reversal episode and trace the
inner disk location.
Title : An X-ray view of the Scary Barbie
PI: Guolo
Abstract: AT2021lwx/ZTF20abrbeie, a.k.a Scary Barbie, is an ultra-luminous
optically discovered transient at z ~ 1 with no previously cataloged
host. It is the most energetic transient ever observed, showing a
single optical brightening by a factor >100 to a luminosity of 7 x
10^(45) erg s^(-1) and a total radiated energy of 1.5 x 10^(53) erg,
both greater than any known optical transient. Very little is known
about its X-ray emission and spectra, but the stacking of recent
Swift/XRT data reveals a detection at an X-ray luminosity > 10^(45)
erg s^(-1), which is brighter than any non-jetted transient. We have
obtained a long XMM observation and aim to use the high sensitivity
and low background of Chandra to track the spectral and luminosity
evolution of the source. We request two visits at +30 days and +80
days from this request, divided in 20ks and 30 ks, respectively.
Title : Determining the jet collimation of the dirty fireball GRB candidate
AT2023lcr
PI: Martin-Carrillo
Abstract: AT2023lcr is a recently discovered fast-fading red transient with
multi-wavelength observations consistent with a typical long gamma-ray
burst (GRB) afterglow at redshift 1.0272. However, no gamma-ray prompt
emission was detected in the direction of the transient. GOTO
observations constrained the window of possible prompt emission
allowing gamma-ray missions to set tight limits on the gamma-ray
emission. Based on these observations, there are two leading possible
scenarios: an on-axis dirty fireball that had its prompt emission
choked or an off-axis GRB with a narrow jet whose prompt emission we
missed. In the case of the dirty fireball, low Lorentz factor implied
by the lack of GRB prompt emission also suggest a weaker jet
collimation. Here we propose to observe the X-ray afterglow of this
rare case of GRB to constrain its jet opening angle and distinguish
between these two models and measure its true energetics.
Title : A Chandra and JWST view of M-dwarf rocky planet atmospheres
PI: Howard
Abstract: One out of four terrestrial planet atmospheres accessible to JWST
orbits a flaring M-dwarf. The X-ray light from these flares drives
variability in planetary atmospheres, breaking apart molecules,
causing atmospheric escape, and complicating interpretation of transit
spectra. Upcoming JWST observations of a rocky exoplanet orbiting the
M-dwarf flare star LTT 1445A provide a unique opportunity to probe the
effects of flares on the planet. These observations are part of the
approved JWST Cycle 1 large program 2512. LTT 1445 is a hierarchical
triple system of mid to late M-dwarfs, with 2 terrestrial planets
transiting the A component on 3.1 and 5.4 d periods. Both components
are confirmed flare stars, as new Chandra observations spatially
resolve A and BC, and observe frequent flares from each. Chandra will
detect ~1 flare in the SXR during the flare-affected period of JWST
observations. We request the first simultaneous X-ray and NIR
observation of activity on a rocky planet atmosphere.
Title : SN 2023ixf: A bright supernova in M101
PI: Chandra
Abstract: Supernova SN 2023ixf has exploded in a nearby galaxy M101 (d=6.4 Mpc),
discovered on 19 May at a magnitude 14.9. It is one of the closest
supernovae found in the past several decades. The optical spectra has
shown flash ionization features indicating of dense circumstellar
medium (CSM), which powers X-ray and radio emission in a supernova.
Thus we are nearly guaranteed to detect X-ray emission, which can
constrain shock energetics and CSM characteristics. As the supernova
is very young, it is expected to evolve fast. Thats why we request for
two epochs. This will provide understanding of circumstellar
interaction evolution with time, which is crucial since they are
connected to the stellar mass-loss at prior to the supernova. We are
also triggering our approved GMRT radio observations and requested for
for VLA DDT time in 2-25 GHz. Swift-XRT observations are approved for
this supernova. However, Chandra is superior to Swif
to provide accurate determination of column density.
Title : SN 2023ixf: A bright supernova in M101
PI: Chandra
Abstract: Supernova SN 2023ixf has exploded in a nearby galaxy M101 (d=6.4 Mpc),
discovered on 19 May at a magnitude 14.9. It is one of the closest
supernovae found in the past several decades. The optical spectra has
shown flash ionization features indicating of dense circumstellar
medium (CSM), which powers X-ray and radio emission in a supernova.
Thus we are nearly guaranteed to detect X-ray emission, which can
constrain shock energetics and CSM characteristics. As the supernova
is very young, it is expected to evolve fast. Thats why we request for
two epochs. This will provide understanding of circumstellar
interaction evolution with time, which is crucial since they are
connected to the stellar mass-loss at prior to the supernova. We are
also triggering our approved GMRT radio observations and requested for
for VLA DDT time in 2-25 GHz. Swift-XRT observations are approved for
this supernova. However, Chandra is superior to Swif
to provide accurate determination of column density.
Title : Understanding the orbital evolution of the repeating partial tidal
disruption: J0456-20
PI: Liu
Abstract: Repeating flares from the centre of galaxies with recurrence times of
months to decades have been reported recently. The total number of
these events is still small, with four reported so far. They are best
explained as repeating partial tidal disruption events (pTDEs).
Compared to normal one-off TDEs, repeating pTDEs are particularly
valuable for studying the accretion process in supermassive black hole
(SMBH)-accreting systems, as multi-wavelength observations can be
efficiently scheduled at different flux level. In addition, they are
also the best candidates to explore the dynamics of tightly bound
stars around SMBHs beyond our own Galaxy. We request three Chandra
observations, i.e. 10ks each for the first two observations and 20ks
for the last observation, to accurately measure the X-ray variability
and precisely locate the position of one of the most well-studied
repeating pTDE candidate J0456-20 during its next flaring period.
Title : Determining the True Energetics of one of the Brightest Gamma-ray
Bursts
PI: Fong
Abstract: GRB 230307A is a recently discovered long-duration gamma-ray burst
(GRB) and represents one of the brightest such events detected in over
50 years of observation. Based on ongoing multi-wavelength
observations, there are two exciting possibilities for this event: it
is the result of a massive star collapse at z>1 which spawned the most
energetic GRB to date, or it is a nearby neutron star merger with a
kilonova detection (the second event in this class). Despite its
gamma-ray brightness, its X-ray and optical afterglows are
comparatively faint requiring the sensitivity of Chandra to monitor
it. Here we propose to monitor the X-ray afterglow of the remarkable
GRB 230307A to constrain its opening angle and thus true energetics.
Title : Determining the True Energetics of one of the Brightest Gamma-ray
Bursts
PI: Fong
Abstract: GRB 230307A is a recently discovered long-duration gamma-ray burst
(GRB) and represents one of the brightest such events detected in over
50 years of observation. Based on ongoing multi-wavelength
observations, there are two exciting possibilities for this event: it
is the result of a massive star collapse at z>1 which spawned the most
energetic GRB to date, or it is a nearby neutron star merger with a
kilonova detection (the second event in this class). Despite its
gamma-ray brightness, its X-ray and optical afterglows are
comparatively faint requiring the sensitivity of Chandra to monitor
it. Here we propose to monitor the X-ray afterglow of the remarkable
GRB 230307A to constrain its opening angle and thus true energetics.
Title : Determining the True Energetics of one of the Brightest Gamma-ray
Bursts
PI: Fong
Abstract: GRB 230307A is a recently discovered long-duration gamma-ray burst
(GRB) and represents one of the brightest such events detected in over
50 years of observation. Based on ongoing multi-wavelength
observations, there are two exciting possibilities for this event: it
is the result of a massive star collapse at z>1 which spawned the most
energetic GRB to date, or it is a nearby neutron star merger with a
kilonova detection (the second event in this class). Despite its
gamma-ray brightness, its X-ray and optical afterglows are
comparatively faint requiring the sensitivity of Chandra to monitor
it. Here we propose to monitor the X-ray afterglow of the remarkable
GRB 230307A to constrain its opening angle and thus true energetics.
Title : Understanding the orbital evolution of the repeating partial tidal
disruption: J0456-20
PI: Liu
Abstract: Repeating flares from the centre of galaxies with recurrence times of
months to decades have been reported recently. The total number of
these events is still small, with four reported so far. They are best
explained as repeating partial tidal disruption events (pTDEs).
Compared to normal one-off TDEs, repeating pTDEs are particularly
valuable for studying the accretion process in supermassive black hole
(SMBH)-accreting systems, as multi-wavelength observations can be
efficiently scheduled at different flux level. In addition, they are
also the best candidates to explore the dynamics of tightly bound
stars around SMBHs beyond our own Galaxy. We request three Chandra
observations, i.e. 10ks each for the first two observations and 20ks
for the last observation, to accurately measure the X-ray variability
and precisely locate the position of one of the most well-studied
repeating pTDE candidate J0456-20 during its next flaring period.
Title : Understanding the orbital evolution of the repeating partial tidal
disruption: J0456-20
PI: Liu
Abstract: Repeating flares from the centre of galaxies with recurrence times of
months to decades have been reported recently. The total number of
these events is still small, with four reported so far. They are best
explained as repeating partial tidal disruption events (pTDEs).
Compared to normal one-off TDEs, repeating pTDEs are particularly
valuable for studying the accretion process in supermassive black hole
(SMBH)-accreting systems, as multi-wavelength observations can be
efficiently scheduled at different flux level. In addition, they are
also the best candidates to explore the dynamics of tightly bound
stars around SMBHs beyond our own Galaxy. We request three Chandra
observations, i.e. 10ks each for the first two observations and 20ks
for the last observation, to accurately measure the X-ray variability
and precisely locate the position of one of the most well-studied
repeating pTDE candidate J0456-20 during its next flaring period.
Title : Which Source is Active in Terzan 5?
PI: Heinke
Abstract: Many globular clusters contain multiple transient LMXBs, identified by
Chandra in e.g. NGC 6440, Liller 1, and Terzan 5. MAXI sees an
outburst from Terzan 5 (Atel 15917, at 89 mCrab), confirmed by Swift
(Atel 15919, Kennea+23), suggested to be Terzan 5 X-3, last seen in
2012. However, the Swift 3.5 error circle includes 5-6 other known
X-ray sources, and the redback MSP Ter 5 P (Bogdanov+21)--possibly a
transitional MSP (only 3 confirmed). We request Chandra to pinpoint
the outbursting LMXB. If we confirm Ter 5 X-3, we will establish its
recurrence time and thus average mass-transfer rate, crucial for
studies of crust and core cooling (e.g. Brown+2018). If it is a new
transient, it will enable e.g. a census of transient LMXBs, their
recurrence rates, the quiescent spectrum, & enable later IR follow-up
(e.g. 30-m class). Radio studies are proposed, but their angular
resolution is less (VLA is in B-config) and Terzan 5 is very complex
in the radio (Urquhart+2020), so Chandra is needed.
Title : High Resolution Spectroscopy of the First Giant Outburst from LS V +44
17
PI: Reynolds
Abstract: The Be/XRB LSV +44 17 is undergoing a type-II outburst for the first
time, with a luminosity near the Eddington limit (fx ~ 3 crab, 15-50
keV). In a BeXRB accreting at Eddington luminosities, we expect the
accretion flow to thicken, accompanied by significant outflows e.g.,
Shakura & Sunyaev (1973). Studies of Be/XRBs promise the opportunity
to learn much about this mode of accretion.
X-ray spectroscopy provides a means to study the innermost regions of
the accretion flow
where the wind will originate. The unique high resolution X-ray
spectroscopy provided by
Chandra/HETGS in the iron K region is the only platform with which to
study disk winds.
Previously a ~3000 km/s outflow has been detected from the BeXRB
1A0535+262 at a
luminosity of 10% Eddington (Reynolds+ 2010). At higher luminosities
still, we may expect
a higher velocity outflow (Higginbottom+ 2019) and these models are
supported by the
discovery of a ~0.2c from Swift J0243.6+6124 (van den Eijnden+ 2019).
Title : Discovery of 12.5 days periodic bumps in the late-time light curves of
a unique type Ic supernova
PI: Chen
Abstract: Neutron stars (NS) or stellar-mass black holes (BH) are thought to be
formed from massive star explosions. People have found indirect
evidence of many tens of stellar-mass BHs, mainly from systems
detected as X-ray transients. However, the immediate connection
between the newly born BH or NS and the supernova explosion has not
been directly observed.
We propose to observe a unique, the-first-of-its-kind supernova SN
2022jli which shows periodic bumps in the optical light curve. The
visible light periodicity is likely induced by an internal engine,
like a binary star in which at least one of the components is a
compact object. Since the visible light periodicity is likely
processed emission of high energy photons from accretion, X-ray
observation is critical for understanding the origin of the
periodicity.
Due to the X-ray background emission from the host galaxy, Chandra's
observation at sub-arcsec resolution is critical to detect the X-ray
emission from the system.
Title : Discovery of 12.5 days periodic bumps in the late-time light curves of
a unique type Ic supernova
PI: Chen
Abstract: Neutron stars (NS) or stellar-mass black holes (BH) are thought to be
formed from massive star explosions. People have found indirect
evidence of many tens of stellar-mass BHs, mainly from systems
detected as X-ray transients. However, the immediate connection
between the newly born BH or NS and the supernova explosion has not
been directly observed.
We propose to observe a unique, the-first-of-its-kind supernova SN
2022jli which shows periodic bumps in the optical light curve. The
visible light periodicity is likely induced by an internal engine,
like a binary star in which at least one of the components is a
compact object. Since the visible light periodicity is likely
processed emission of high energy photons from accretion, X-ray
observation is critical for understanding the origin of the
periodicity.
Due to the X-ray background emission from the host galaxy, Chandra's
observation at sub-arcsec resolution is critical to detect the X-ray
emission from the system.
Title : Discovery of 12.5 days periodic bumps in the late-time light curves of
a unique type Ic supernova
PI: Chen
Abstract: Neutron stars (NS) or stellar-mass black holes (BH) are thought to be
formed from massive star explosions. People have found indirect
evidence of many tens of stellar-mass BHs, mainly from systems
detected as X-ray transients. However, the immediate connection
between the newly born BH or NS and the supernova explosion has not
been directly observed.
We propose to observe a unique, the-first-of-its-kind supernova SN
2022jli which shows periodic bumps in the optical light curve. The
visible light periodicity is likely induced by an internal engine,
like a binary star in which at least one of the components is a
compact object. Since the visible light periodicity is likely
processed emission of high energy photons from accretion, X-ray
observation is critical for understanding the origin of the
periodicity.
Due to the X-ray background emission from the host galaxy, Chandra's
observation at sub-arcsec resolution is critical to detect the X-ray
emission from the system.
Title : Discovery of Minute-timescale Flares in the Aftermath of a Cosmic
Explosion
PI: Ho
Abstract: Over the past week we detected minute-timescale optical flares with
supernova-like luminosities associated with a 100-day old transient at
z=0.256. Our discovery has no precedent, and the simplest explanation
is blazar-like activity, i.e., an on-axis relativistic jet powered by
a black hole. However, unlike in TDEs, this black hole would have to
be either stellar-mass or intermediate-mass. A basic prediction of the
blazar model is coincident X-ray flares. We request Chandra
observations within the next two weeks to search for the predicted
X-ray flares. Chandra is the only facility with the required
sensitivity.
Title : Discovery of Minute-timescale Flares in the Aftermath of a Cosmic
Explosion
PI: Ho
Abstract: Over the past week we detected minute-timescale optical flares with
supernova-like luminosities associated with a 100-day old transient at
z=0.256. Our discovery has no precedent, and the simplest explanation
is blazar-like activity, i.e., an on-axis relativistic jet powered by
a black hole. However, unlike in TDEs, this black hole would have to
be either stellar-mass or intermediate-mass. A basic prediction of the
blazar model is coincident X-ray flares. We request Chandra
observations within the next two weeks to search for the predicted
X-ray flares. Chandra is the only facility with the required
sensitivity.
Title : A red giant orbiting a black hole
PI: El-Badry
Abstract: We propose 20ks ACIS observations of a newly-discovered black hole +
red giant binary only 1 kpc from Earth. We identified the binary
through Gaia DR3 astrometry. Our spectroscopic follow-up has recently
validated the Gaia orbital solution and shown this object to be one of
only two high-probability black hole candidates among ~1 million
binary star orbital solutions published in DR3. The orbital period --
1270 days -- is much longer than that of any known black hole binary.
Nevertheless, accretion of the giant's wind by the BH will lead to
detectable X-rays for any radiative efficiency above 10^-4. The
periastron passage -- when the X-ray flux is expected to peak -- will
occur in February 2022. The next passage will not occur until 2026,
motivating rapid response now. These observations will enable prompt
publication of the 2nd unambiguous dormant black hole in the Milky Way
and offer good odds for X-ray detection of the BH with the lowest
known accretion rate.
Title : Flux Limits on the Nearest Black Hole: Gaia BH1
PI: Rodriguez
Abstract: The Milky Way is thought to contain about 1e8 stellar mass black holes
(BHs). However, only ~20 BHs are dynamically confirmed. Almost all of
these are accreting from a companion and were discovered via X-rays.
By calculating astrometric orbits for ~ 1e5 binaries, the recent 3rd
Gaia data release yielded a single unambiguous dormant BH: Gaia BH1. A
bright (G=13.8), slowly-rotating G2 star orbits a 10 Msun BH with an
orbital period of 186 days, much longer than the periods of X-ray
binaries. At d=480 pc, the system is the closest known BH by a factor
of 3. This implies that although wide, dormant BHs are difficult to
detect, they are significantly more abundant than their accreting,
X-ray bright cousins. The G2 donor star ejects mass through winds that
should accrete onto the BH with an unknown efficiency. A deep Chandra
ACIS observation will constrain the accretion efficiency of this
system, thus probing the physics of accretion in this new and unique
population of BHs.
Title : Mapping the dust along the line of sight to GRB221009A
PI: Heinz
Abstract: Bright X-ray transients can cause extended ring-like dust scattering
echoes in the Galactic plane. Tomography of these echoes allows
accurate distance measurements and studies of dust mineralogy and
distribution. GRB221009A was among the brightest bursts in recent
history and at a Galactic latitude of 4.25 degrees, has produced a
bright ring echo detected with Swift. We propose to follow up this
detection using Chandra to measure the distance to the dust clouds
along the line of sight with unprecedented accuracy and to perform
measurements of dust-to-gas ratios of different interstellar clouds by
matching the observed dust to CO data to be obtained from the IRAM 30m
dish. Only Chandra has the angular resolution to take advantage of how
narrow these rings are expected to be, given how short gamma ray
bursts typically are.
Title : First Look at an Extremely Reddened Lensed Quasar Image
PI: Pooley
Abstract: We have discovered what is likely the most highly reddened lensed
quasar image, which has the potential to give what may be the best
reddening curve ever obtained for a z~0.5 galaxy. Lensing models
predict that the close pair of images (about 0.6 arcseconds apart)
should be comparable in brightness, but i band imaging with IMACS
reveals that one image is nearly 100 times fainter than the other of
the close pair. X-ray imaging is needed to determine what role
microlensing might play in the flux ratio anomaly and how much is due
to a dust lane in the lensing galaxy. A pointed ROSAT/PSPC caught the
object at the very edge of the field of view, but the vignetting
effects are severe and uncertain. A brief Chandra observation now
will let us assess the feasibility of a Cycle 25 proposal for a deeper
observation.
Title : Flux Limits on the Nearest Black Hole: Gaia BH1
PI: Rodriguez
Abstract: The Milky Way is thought to contain about 1e8 stellar mass black holes
(BHs). However, only ~20 BHs are dynamically confirmed. Almost all of
these are accreting from a companion and were discovered via X-rays.
By calculating astrometric orbits for ~ 1e5 binaries, the recent 3rd
Gaia data release yielded a single unambiguous dormant BH: Gaia BH1. A
bright (G=13.8), slowly-rotating G2 star orbits a 10 Msun BH with an
orbital period of 186 days, much longer than the periods of X-ray
binaries. At d=480 pc, the system is the closest known BH by a factor
of 3. This implies that although wide, dormant BHs are difficult to
detect, they are significantly more abundant than their accreting,
X-ray bright cousins. The G2 donor star ejects mass through winds that
should accrete onto the BH with an unknown efficiency. A deep Chandra
ACIS observation will constrain the accretion efficiency of this
system, thus probing the physics of accretion in this new and unique
population of BHs.
Title : Chandra observation of possible nuclear transient in NGC 7793
PI: Brightman
Abstract: We have recently reported the discovery of a nuclear transient in the
nearby galaxy NGC 7793 (3.8 Mpc), serendipitously detected by
Swift/XRT (https://www.astronomerstelegram.org/?read=15632). The X-ray
source was not detected with Swift only two weeks prior, however a
Chandra source with a flux 3 orders of magnitude lower than seen has
been reported at the position of the Swift/XRT source. While this
appears to be a nuclear transient, the luminosity of 3.8x10^39 erg/s
does not preclude a transient ULX. The source position, with a Swift
positional accuracy of 3 arcsec, could plausibly be outside the
nucleus. However, a much more precise position with Chandra could rule
out the nucleus, implying a ULX, or narrow the position down to the
nucleus implying a TDE is more likely.
Title : Pinpointing the Super-Massive Black Hole Leo I*
PI: Pacucci
Abstract: The presence of an SMBH of ~3 million solar masses (Leo I*) was
recently suggested via dynamical measurements at the center of the
local dwarf spheroidal galaxy Leo I. Due to the lack of gas in Leo I,
the only channel available to feed the SMBH and, thus, produce an
electromagnetic signature is via mass loss from red giant branch (RGB)
stars.
XMM-Newton detected an X-ray source (4XMM J100825.8+121839) ~15'', or
~18 pc, away from the dynamical center of Leo I. This source has an
[0.5-4.5] keV flux of ~4 x 10^-15 erg/s/cm^2, in agreement with our
prediction for the flux of the source. The dynamical center of Leo I,
which is a good proxy for the plausible location of the SMBH in Leo I,
has an uncertainty of ~10'', which makes the identification of this
source with the electromagnetic signature of Leo I* even more
tantalizing.
We request an 80 ks ACIS-S observation to locate the position of the
X-ray source with a precision < 0.5'' as soon as it becomes observable
by Chandra (10-14-2022).
Title : Localisation of new X-ray transient Swift J023017.0+283603
PI: Evans
Abstract: Swift J023017.0+283603 is an X-ray transient detected by Swift-XRT
(ATEL 15454). Originally it was thought to be a TDE due to positional
coincidence with galaxy at z~0.035, and its very soft, thermal
spectrum. This has now been ruled out by its temporal behaviour, which
shows episodes of high flux (L~2e42 erg/s) followed by periods of
non-detection with limits around 1e41 erg/s.
The outburst is only seen in X-rays, and the best X-ray position, from
Swift-XRT is consistent both with the nucleus of the putative host,
2MASX J02301709+2836050, and also with a two year-old supernova, SN
2020rht. Chandra is the only facility capable of giving a localisation
of this object accurate enough to unambigously confirm the association
with the nucleus, supernova, or neither, which is vital to determine
the nature of this enigmatic object.
Title : Evaporation of a habitable-zone exoplanet with a water envelope
PI: Poppenhaeger
Abstract: We request a short (10ks) Chandra-HRC-S observation of a recently
discovered exoplanet which resides in the habitable zone around a
near-by M dwarf and has a density consistent with a thick water
envelope. An X-ray observation would allow us to measure the stellar
X-ray flux irradiating the planet, which is the driver of atmospheric
evaporation of exoplanets. Current upper limits for the host star are
only available from ROSAT and are uninformatively high (with ca. 5e27
erg/s). The anticipated measurement (allowing a detection down to Lx =
3e26 erg/s, practically guaranteeing a detection for an M dwarf) would
tell us whether this exoplanet is subject to a similar X-ray flux like
the small exoplanet GJ 436 b, which shows a huge atmospheric
evaporation tail. If so, this planet could be followed up meaningfully
at other wavelengths to test for the presence and density of its
evaporation plume and constrain habitability.
Title : Localizing an unusual long-lived faint X-ray transient
PI: Maccarone
Abstract: Through the Swift Galactic Bulge Survey, we have discovered an X-ray
transient that has been on for over a year, but that has never gotten
particularly bright (0.2-0.6 cts/sec with Swift). The Swift positions
are inadequate for reliable identification of its optical counterpart.
It is likely a type of symbiotic X-ray binary activity not seen before
and there is a red giant within the error box. As symbiotic X-ray
binaries are an important stage in the evolution of LISA-band sources,
this is an important phenomenon to understand. We request a short
Chandra observation to localize the source.
Title : Pinpointing the Super-Massive Black Hole Leo I*
PI: Pacucci
Abstract: The presence of an SMBH of ~3 million solar masses (Leo I*) was
recently suggested via dynamical measurements at the center of the
local dwarf spheroidal galaxy Leo I. Due to the lack of gas in Leo I,
the only channel available to feed the SMBH and, thus, produce an
electromagnetic signature is via mass loss from red giant branch (RGB)
stars.
XMM-Newton detected an X-ray source (4XMM J100825.8+121839) ~15'', or
~18 pc, away from the dynamical center of Leo I. This source has an
[0.5-4.5] keV flux of ~4 x 10^-15 erg/s/cm^2, in agreement with our
prediction for the flux of the source. The dynamical center of Leo I,
which is a good proxy for the plausible location of the SMBH in Leo I,
has an uncertainty of ~10'', which makes the identification of this
source with the electromagnetic signature of Leo I* even more
tantalizing.
We request an 80 ks ACIS-S observation to locate the position of the
X-ray source with a precision < 0.5'' as soon as it becomes observable
by Chandra (10-14-2022).
Title : Confirmation of a magnetar driving an extremely long GRB
PI: Gompertz
Abstract: Ultra-long GRBs, with durations well in excess of a thousand seconds,
are believed to be driven by rapidly-rotating and highly magnetised
neutron stars known as magnetars. Evidence for this comes from the
unusually luminous SN 2011kl, associated with ULGRB 111209A, which
could not be explained with a plausible 56Ni model. Here, we request
observations of ULGRB 220706A, which shows evidence for a magnetar
engine in the GRB itself. It exhibits a late, long-lived energy
injection plateau that is consistent with dipole spin-down, and a
possible periodic signature of 3.5ms. The burst also shows a candidate
emission line during late flaring activity.
No optical counterpart has been identified, so the best localisation
comes from Swift-XRT, which is imprecise. Chandra observations can
improve the localisation so that an association with a host can be
made and a redshift obtained. They can also confirm that our
unprecendented long-lived plateau is not due to a contaminating
background source.
Title : X-ray driven chemistry in the protoplanetary disk of DQ Tau
PI: Getman
Abstract: X-ray flares are expected to induce time-variable ion-molecular
chemistry in young protoplanetary disks. DQ Tau is a young, high
eccentricity binary that exhibits flux increases in
X-ray/optical/mm-band near periastron and offers a unique laboratory
for gas-phase ion disk chemistry. We won ALMA program to observe the
reaction of molecular line emission to ionizing radiation across one
binary orbit. Complementary to the approved NuSTAR/Swift observations
near periastron, we request Chandra snapshots away from periastron to
measure X-ray fluxes as inputs to a time-resolved physical-chemical
disk model. The model and ALMA data will provide unique estimates of
disk density distribution that have far-reaching implications for
understanding evolution of disks and formation of planets.
Title : X-ray driven chemistry in the protoplanetary disk of DQ Tau
PI: Getman
Abstract: X-ray flares are expected to induce time-variable ion-molecular
chemistry in young protoplanetary disks. DQ Tau is a young, high
eccentricity binary that exhibits flux increases in
X-ray/optical/mm-band near periastron and offers a unique laboratory
for gas-phase ion disk chemistry. We won ALMA program to observe the
reaction of molecular line emission to ionizing radiation across one
binary orbit. Complementary to the approved NuSTAR/Swift observations
near periastron, we request Chandra snapshots away from periastron to
measure X-ray fluxes as inputs to a time-resolved physical-chemical
disk model. The model and ALMA data will provide unique estimates of
disk density distribution that have far-reaching implications for
understanding evolution of disks and formation of planets.
Title : X-ray driven chemistry in the protoplanetary disk of DQ Tau
PI: Getman
Abstract: X-ray flares are expected to induce time-variable ion-molecular
chemistry in young protoplanetary disks. DQ Tau is a young, high
eccentricity binary that exhibits flux increases in
X-ray/optical/mm-band near periastron and offers a unique laboratory
for gas-phase ion disk chemistry. We won ALMA program to observe the
reaction of molecular line emission to ionizing radiation across one
binary orbit. Complementary to the approved NuSTAR/Swift observations
near periastron, we request Chandra snapshots away from periastron to
measure X-ray fluxes as inputs to a time-resolved physical-chemical
disk model. The model and ALMA data will provide unique estimates of
disk density distribution that have far-reaching implications for
understanding evolution of disks and formation of planets.
Title : X-ray driven chemistry in the protoplanetary disk of DQ Tau
PI: Getman
Abstract: X-ray flares are expected to induce time-variable ion-molecular
chemistry in young protoplanetary disks. DQ Tau is a young, high
eccentricity binary that exhibits flux increases in
X-ray/optical/mm-band near periastron and offers a unique laboratory
for gas-phase ion disk chemistry. We won ALMA program to observe the
reaction of molecular line emission to ionizing radiation across one
binary orbit. Complementary to the approved NuSTAR/Swift observations
near periastron, we request Chandra snapshots away from periastron to
measure X-ray fluxes as inputs to a time-resolved physical-chemical
disk model. The model and ALMA data will provide unique estimates of
disk density distribution that have far-reaching implications for
understanding evolution of disks and formation of planets.
Title : X-ray driven chemistry in the protoplanetary disk of DQ Tau
PI: Getman
Abstract: X-ray flares are expected to induce time-variable ion-molecular
chemistry in young protoplanetary disks. DQ Tau is a young, high
eccentricity binary that exhibits flux increases in
X-ray/optical/mm-band near periastron and offers a unique laboratory
for gas-phase ion disk chemistry. We won ALMA program to observe the
reaction of molecular line emission to ionizing radiation across one
binary orbit. Complementary to the approved NuSTAR/Swift observations
near periastron, we request Chandra snapshots away from periastron to
measure X-ray fluxes as inputs to a time-resolved physical-chemical
disk model. The model and ALMA data will provide unique estimates of
disk density distribution that have far-reaching implications for
understanding evolution of disks and formation of planets.
Title : X-ray driven chemistry in the protoplanetary disk of DQ Tau
PI: Getman
Abstract: X-ray flares are expected to induce time-variable ion-molecular
chemistry in young protoplanetary disks. DQ Tau is a young, high
eccentricity binary that exhibits flux increases in
X-ray/optical/mm-band near periastron and offers a unique laboratory
for gas-phase ion disk chemistry. We won ALMA program to observe the
reaction of molecular line emission to ionizing radiation across one
binary orbit. Complementary to the approved NuSTAR/Swift observations
near periastron, we request Chandra snapshots away from periastron to
measure X-ray fluxes as inputs to a time-resolved physical-chemical
disk model. The model and ALMA data will provide unique estimates of
disk density distribution that have far-reaching implications for
understanding evolution of disks and formation of planets.
Title : X-ray driven chemistry in the protoplanetary disk of DQ Tau
PI: Getman
Abstract: X-ray flares are expected to induce time-variable ion-molecular
chemistry in young protoplanetary disks. DQ Tau is a young, high
eccentricity binary that exhibits flux increases in
X-ray/optical/mm-band near periastron and offers a unique laboratory
for gas-phase ion disk chemistry. We won ALMA program to observe the
reaction of molecular line emission to ionizing radiation across one
binary orbit. Complementary to the approved NuSTAR/Swift observations
near periastron, we request Chandra snapshots away from periastron to
measure X-ray fluxes as inputs to a time-resolved physical-chemical
disk model. The model and ALMA data will provide unique estimates of
disk density distribution that have far-reaching implications for
understanding evolution of disks and formation of planets.
Title : X-ray driven chemistry in the protoplanetary disk of DQ Tau
PI: Getman
Abstract: X-ray flares are expected to induce time-variable ion-molecular
chemistry in young protoplanetary disks. DQ Tau is a young, high
eccentricity binary that exhibits flux increases in
X-ray/optical/mm-band near periastron and offers a unique laboratory
for gas-phase ion disk chemistry. We won ALMA program to observe the
reaction of molecular line emission to ionizing radiation across one
binary orbit. Complementary to the approved NuSTAR/Swift observations
near periastron, we request Chandra snapshots away from periastron to
measure X-ray fluxes as inputs to a time-resolved physical-chemical
disk model. The model and ALMA data will provide unique estimates of
disk density distribution that have far-reaching implications for
understanding evolution of disks and formation of planets.
Title : X-ray driven chemistry in the protoplanetary disk of DQ Tau
PI: Getman
Abstract: X-ray flares are expected to induce time-variable ion-molecular
chemistry in young protoplanetary disks. DQ Tau is a young, high
eccentricity binary that exhibits flux increases in
X-ray/optical/mm-band near periastron and offers a unique laboratory
for gas-phase ion disk chemistry. We won ALMA program to observe the
reaction of molecular line emission to ionizing radiation across one
binary orbit. Complementary to the approved NuSTAR/Swift observations
near periastron, we request Chandra snapshots away from periastron to
measure X-ray fluxes as inputs to a time-resolved physical-chemical
disk model. The model and ALMA data will provide unique estimates of
disk density distribution that have far-reaching implications for
understanding evolution of disks and formation of planets.
Title : X-ray driven chemistry in the protoplanetary disk of DQ Tau
PI: Getman
Abstract: X-ray flares are expected to induce time-variable ion-molecular
chemistry in young protoplanetary disks. DQ Tau is a young, high
eccentricity binary that exhibits flux increases in
X-ray/optical/mm-band near periastron and offers a unique laboratory
for gas-phase ion disk chemistry. We won ALMA program to observe the
reaction of molecular line emission to ionizing radiation across one
binary orbit. Complementary to the approved NuSTAR/Swift observations
near periastron, we request Chandra snapshots away from periastron to
measure X-ray fluxes as inputs to a time-resolved physical-chemical
disk model. The model and ALMA data will provide unique estimates of
disk density distribution that have far-reaching implications for
understanding evolution of disks and formation of planets.
Title : X-ray driven chemistry in the protoplanetary disk of DQ Tau
PI: Getman
Abstract: X-ray flares are expected to induce time-variable ion-molecular
chemistry in young protoplanetary disks. DQ Tau is a young, high
eccentricity binary that exhibits flux increases in
X-ray/optical/mm-band near periastron and offers a unique laboratory
for gas-phase ion disk chemistry. We won ALMA program to observe the
reaction of molecular line emission to ionizing radiation across one
binary orbit. Complementary to the approved NuSTAR/Swift observations
near periastron, we request Chandra snapshots away from periastron to
measure X-ray fluxes as inputs to a time-resolved physical-chemical
disk model. The model and ALMA data will provide unique estimates of
disk density distribution that have far-reaching implications for
understanding evolution of disks and formation of planets.
Title : X-ray driven chemistry in the protoplanetary disk of DQ Tau
PI: Getman
Abstract: X-ray flares are expected to induce time-variable ion-molecular
chemistry in young protoplanetary disks. DQ Tau is a young, high
eccentricity binary that exhibits flux increases in
X-ray/optical/mm-band near periastron and offers a unique laboratory
for gas-phase ion disk chemistry. We won ALMA program to observe the
reaction of molecular line emission to ionizing radiation across one
binary orbit. Complementary to the approved NuSTAR/Swift observations
near periastron, we request Chandra snapshots away from periastron to
measure X-ray fluxes as inputs to a time-resolved physical-chemical
disk model. The model and ALMA data will provide unique estimates of
disk density distribution that have far-reaching implications for
understanding evolution of disks and formation of planets.
Title : A precise position for the likely very local GRB 220611A
PI: Levan
Abstract: GRB 220611A is a long duration GRB located 15 from an S0 galaxy at a
distance of only 220 Mpc (the third closest GRB in 18 years of Swift
operations). It has a very low probability of chance alignment (0.3%).
However, the host galaxy shows no sign of star formation, and the
offset is more in keeping with short GRBs formed from compact object
mergers than from long bursts formed from collapsars. Recent evidence
suggests that long bursts can be formed from mergers, and so this is a
plausible channel for GRB 220611A. The RA of the burst is such that it
cannot be viewed from the ground, and so we currently lack an accurate
position. However, Chandra observations can pinpoint the afterglow
within its host, revealing any star formation at the burst location,
or a more distant galaxy should the burst arise from a chance
alignment. Such a precise position can therefore greatly enhance (or
repudiate) the possibility that the burst is at 220 Mpc and inform the
collapsar/merger origin.
Title : Disk winds in IGR J17091-3624 in the exotic variability state
PI: Wang
Abstract: IGRJ17091-3624 is a peculiar black hole binary (BHB) as it exhibits
exotic variability patterns that are highly structured, very similar
to GRS 1915+105. After the two major outbursts in 2011 and 2016,
IGRJ17091-3624 went into a new outburst in March 2022. With our NICER
and NuSTAR campaign, we observe Fe XXV and Fe XXVI absorption lines in
NICER spectra in the exotic variability state. These absorption lines
indicate the presence of disk winds, which are crucial to understand
the nature of the exotic variability of accretion flow thought to be
due to disk instability either because the black hole accretes at a
high mass accretion rate close to the Eddington limit, or disk
tearing. We request 1 Chandra/HETG observation of 30 ks to study the
disk winds in IGRJ17091-3624 in its current exotic variability state.
Joint observations with our approved NICER and NuSTAR GO program
(#5118) are highly favored.
Title : Chandra high-resolution imaging of a new transient ultraluminous X-ray
source in M81
PI: Brightman
Abstract: We propose a Chandra DDT observation of a newly discovered X-ray
source in the nearby (3.7 Mpc) spiral galaxy M81. The source seems to
be a new ultraluminous X-ray source (ULX) that has recently appeared,
never before detected, despite numerous X-ray observations of the
galaxy. This source is one of a handful of transient ULXs we have
discovered recently while searching through Swift/XRT observations.
These new ULXs appear to lie among an older stellar population, where
models imply neutron star accretors are dominant. Unlike the previous
sources identified, M81 has ample HST coverage allowing a search for
an optical counterpart, and to age the stellar population of its
environment. There are also candidate optical transients from ZTF in
the Swift localization region. A 10-ks Chandra observation will
provide the accurate X-ray position to identify the counterpart.
Title : Confirmation of a candidate nearby off-axis short GRB
PI: Gompertz
Abstract: GRB 220412B is an extremely short duration gamma-ray burst lasting
just 140ms. Prompt X-ray and optical follow-up revealed no
corresponding afteglow to deep limits at early times. However, our VLA
observations at 10 days after trigger reveal a bright (~380 uJy)
uncataloged radio source offset just a few arcseconds from the center
of the BAT localisation. These observations are consistent with an
`off-axis' GRB wherein the jet is not directly pointed towards Earth.
The afterglow is initially beamed away from the observer and is later
seen to rise as the relativistic Doppler beaming lessens. The radio
source is not coincident with any known galaxy nor optical emission in
archival images. We therefore request observations with Chandra to
explore its multi-wavelength properties and potentially confirm it as
the GRB afterglow in the local Universe.
Title : A Chandra and ALMA View of the Origin and Impact of M-dwarf Flares
PI: Howard
Abstract: Recently, a large millimeter flare was detected from Proxima Cen.
Since little is known about millimeter flares, we have been awarded 40
hours of upcoming ALMA Cycle 8 observations to determine UV-millimeter
flare relationships using nearby M-dwarfs of various ages and activity
levels. We propose simultaneous ACIS HETG observations of the most
active target (Wolf 359) to constrain the high-energy spectral
properties of millimeter flares and their potential impact on planets.
We apply for DDT time as the ALMA scheduling will occur soon. Previous
observations of Proxima Cen by Chandra and ALMA show X-ray and
millimeter flares trace each other closely, and this proposed study
will help determine if this is a universal property of mid-M dwarfs
regardless of age, thereby creating a powerful new tool to determine
the high-energy environment of stars.
Title : A Chandra and ALMA View of the Origin and Impact of M-dwarf Flares
PI: Howard
Abstract: Recently, a large millimeter flare was detected from Proxima Cen.
Since little is known about millimeter flares, we have been awarded 40
hours of upcoming ALMA Cycle 8 observations to determine UV-millimeter
flare relationships using nearby M-dwarfs of various ages and activity
levels. We propose simultaneous ACIS HETG observations of the most
active target (Wolf 359) to constrain the high-energy spectral
properties of millimeter flares and their potential impact on planets.
We apply for DDT time as the ALMA scheduling will occur soon. Previous
observations of Proxima Cen by Chandra and ALMA show X-ray and
millimeter flares trace each other closely, and this proposed study
will help determine if this is a universal property of mid-M dwarfs
regardless of age, thereby creating a powerful new tool to determine
the high-energy environment of stars.
Title : A Chandra and ALMA View of the Origin and Impact of M-dwarf Flares
PI: Howard
Abstract: Recently, a large millimeter flare was detected from Proxima Cen.
Since little is known about millimeter flares, we have been awarded 40
hours of upcoming ALMA Cycle 8 observations to determine UV-millimeter
flare relationships using nearby M-dwarfs of various ages and activity
levels. We propose simultaneous ACIS HETG observations of the most
active target (Wolf 359) to constrain the high-energy spectral
properties of millimeter flares and their potential impact on planets.
We apply for DDT time as the ALMA scheduling will occur soon. Previous
observations of Proxima Cen by Chandra and ALMA show X-ray and
millimeter flares trace each other closely, and this proposed study
will help determine if this is a universal property of mid-M dwarfs
regardless of age, thereby creating a powerful new tool to determine
the high-energy environment of stars.
Title : A Delayed Jet in a Tidal Disruption Event
PI: Cendes
Abstract: We request a 15 ksec DDT observation of the tidal disruption event
(TDE) AT2018hyz, which has begun rapidly brightening in the radio/mm
~2.2 years post-disruption despite no prior radio detections. Our
radio/mm data are potentially indicative of a relativistic jet
launched with an unexpectedly long delay relative to the time of
disruption, making this the first TDE with evidence for a delayed jet
(and only the second relativistic jet overall). Because the
synchrotron cooling frequency lies above the radio/mm band, Chandra
observations are crucial to pinpoint its location in order to
determine if the outflow is in equipartition, and to accurately
determine its radius, velocity, and energy, as well as the ambient
density around the supermassive black hole. If the Chandra
observations confirm a delayed relativistic outflow, this would
indicate that TDE jets can be produced at low accretion rates rather
than in the early super-Eddington phase.
Title : Probing the X-rays from an unprecedented SMBH Binary at the Last
Inspiraling Stage
PI: Jiang
Abstract: We have recently discovered the first likely SMBH merger event ever
discovered in human history. The final merger will happen within three
years, maybe as short as three months. High-quality X-ray spectra
might be one of the most powerful electromagnetic signal to study the
last inspiraling stage. Our requested XMM-Newton ToO observations on
Dec.31 and Jan.19 have unveiled ultra-high velocity (>0.1c) absorbers
with drastic change, that is natural in binary scenario but never been
seen in normal AGNs. Chandra turns out to be the only facility which
can further monitor the unprecedented target with high-quality spectra
in the next five months (from Feb. To June, visibility gap for
XMM-Newton). Hopefully Chandra will contribute significantly to
confirm the first SMBH binary merger event and explore high energy
physical process happening during the final stage of the binary
inspiral.
Title : Probing the X-rays from an unprecedented SMBH Binary at the Last
Inspiraling Stage
PI: Jiang
Abstract: We have recently discovered the first likely SMBH merger event ever
discovered in human history. The final merger will happen within three
years, maybe as short as three months. High-quality X-ray spectra
might be one of the most powerful electromagnetic signal to study the
last inspiraling stage. Our requested XMM-Newton ToO observations on
Dec.31 and Jan.19 have unveiled ultra-high velocity (>0.1c) absorbers
with drastic change, that is natural in binary scenario but never been
seen in normal AGNs. Chandra turns out to be the only facility which
can further monitor the unprecedented target with high-quality spectra
in the next five months (from Feb. To June, visibility gap for
XMM-Newton). Hopefully Chandra will contribute significantly to
confirm the first SMBH binary merger event and explore high energy
physical process happening during the final stage of the binary
inspiral.
Title : Probing the X-rays from an unprecedented SMBH Binary at the Last
Inspiraling Stage
PI: Jiang
Abstract: We have recently discovered the first likely SMBH merger event ever
discovered in human history. The final merger will happen within three
years, maybe as short as three months. High-quality X-ray spectra
might be one of the most powerful electromagnetic signal to study the
last inspiraling stage. Our requested XMM-Newton ToO observations on
Dec.31 and Jan.19 have unveiled ultra-high velocity (>0.1c) absorbers
with drastic change, that is natural in binary scenario but never been
seen in normal AGNs. Chandra turns out to be the only facility which
can further monitor the unprecedented target with high-quality spectra
in the next five months (from Feb. To June, visibility gap for
XMM-Newton). Hopefully Chandra will contribute significantly to
confirm the first SMBH binary merger event and explore high energy
physical process happening during the final stage of the binary
inspiral.
Title : Probing the X-rays from an unprecedented SMBH Binary at the Last
Inspiraling Stage
PI: Jiang
Abstract: We have recently discovered the first likely SMBH merger event ever
discovered in human history. The final merger will happen within three
years, maybe as short as three months. High-quality X-ray spectra
might be one of the most powerful electromagnetic signal to study the
last inspiraling stage. Our requested XMM-Newton ToO observations on
Dec.31 and Jan.19 have unveiled ultra-high velocity (>0.1c) absorbers
with drastic change, that is natural in binary scenario but never been
seen in normal AGNs. Chandra turns out to be the only facility which
can further monitor the unprecedented target with high-quality spectra
in the next five months (from Feb. To June, visibility gap for
XMM-Newton). Hopefully Chandra will contribute significantly to
confirm the first SMBH binary merger event and explore high energy
physical process happening during the final stage of the binary
inspiral.
Title : Probing the X-rays from an unprecedented SMBH Binary at the Last
Inspiraling Stage
PI: Jiang
Abstract: We have recently discovered the first likely SMBH merger event ever
discovered in human history. The final merger will happen within three
years, maybe as short as three months. High-quality X-ray spectra
might be one of the most powerful electromagnetic signal to study the
last inspiraling stage. Our requested XMM-Newton ToO observations on
Dec.31 and Jan.19 have unveiled ultra-high velocity (>0.1c) absorbers
with drastic change, that is natural in binary scenario but never been
seen in normal AGNs. Chandra turns out to be the only facility which
can further monitor the unprecedented target with high-quality spectra
in the next five months (from Feb. To June, visibility gap for
XMM-Newton). Hopefully Chandra will contribute significantly to
confirm the first SMBH binary merger event and explore high energy
physical process happening during the final stage of the binary
inspiral.
Title : Probing the X-rays from an unprecedented SMBH Binary at the Last
Inspiraling Stage
PI: Jiang
Abstract: We have recently discovered the first likely SMBH merger event ever
discovered in human history. The final merger will happen within three
years, maybe as short as three months. High-quality X-ray spectra
might be one of the most powerful electromagnetic signal to study the
last inspiraling stage. Our requested XMM-Newton ToO observations on
Dec.31 and Jan.19 have unveiled ultra-high velocity (>0.1c) absorbers
with drastic change, that is natural in binary scenario but never been
seen in normal AGNs. Chandra turns out to be the only facility which
can further monitor the unprecedented target with high-quality spectra
in the next five months (from Feb. To June, visibility gap for
XMM-Newton). Hopefully Chandra will contribute significantly to
confirm the first SMBH binary merger event and explore high energy
physical process happening during the final stage of the binary
inspiral.
Title : Probing the X-rays from an unprecedented SMBH Binary at the Last
Inspiraling Stage
PI: Jiang
Abstract: We have recently discovered the first likely SMBH merger event ever
discovered in human history. The final merger will happen within three
years, maybe as short as three months. High-quality X-ray spectra
might be one of the most powerful electromagnetic signal to study the
last inspiraling stage. Our requested XMM-Newton ToO observations on
Dec.31 and Jan.19 have unveiled ultra-high velocity (>0.1c) absorbers
with drastic change, that is natural in binary scenario but never been
seen in normal AGNs. Chandra turns out to be the only facility which
can further monitor the unprecedented target with high-quality spectra
in the next five months (from Feb. To June, visibility gap for
XMM-Newton). Hopefully Chandra will contribute significantly to
confirm the first SMBH binary merger event and explore high energy
physical process happening during the final stage of the binary
inspiral.
Title : Probing the X-rays from an unprecedented SMBH Binary at the Last
Inspiraling Stage
PI: Jiang
Abstract: We have recently discovered the first likely SMBH merger event ever
discovered in human history. The final merger will happen within three
years, maybe as short as three months. High-quality X-ray spectra
might be one of the most powerful electromagnetic signal to study the
last inspiraling stage. Our requested XMM-Newton ToO observations on
Dec.31 and Jan.19 have unveiled ultra-high velocity (>0.1c) absorbers
with drastic change, that is natural in binary scenario but never been
seen in normal AGNs. Chandra turns out to be the only facility which
can further monitor the unprecedented target with high-quality spectra
in the next five months (from Feb. To June, visibility gap for
XMM-Newton). Hopefully Chandra will contribute significantly to
confirm the first SMBH binary merger event and explore high energy
physical process happening during the final stage of the binary
inspiral.
Title : Probing the X-rays from an unprecedented SMBH Binary at the Last
Inspiraling Stage
PI: Jiang
Abstract: We have recently discovered the first likely SMBH merger event ever
discovered in human history. The final merger will happen within three
years, maybe as short as three months. High-quality X-ray spectra
might be one of the most powerful electromagnetic signal to study the
last inspiraling stage. Our requested XMM-Newton ToO observations on
Dec.31 and Jan.19 have unveiled ultra-high velocity (>0.1c) absorbers
with drastic change, that is natural in binary scenario but never been
seen in normal AGNs. Chandra turns out to be the only facility which
can further monitor the unprecedented target with high-quality spectra
in the next five months (from Feb. To June, visibility gap for
XMM-Newton). Hopefully Chandra will contribute significantly to
confirm the first SMBH binary merger event and explore high energy
physical process happening during the final stage of the binary
inspiral.
Title : Probing the X-rays from an unprecedented SMBH Binary at the Last
Inspiraling Stage
PI: Jiang
Abstract: We have recently discovered the first likely SMBH merger event ever
discovered in human history. The final merger will happen within three
years, maybe as short as three months. High-quality X-ray spectra
might be one of the most powerful electromagnetic signal to study the
last inspiraling stage. Our requested XMM-Newton ToO observations on
Dec.31 and Jan.19 have unveiled ultra-high velocity (>0.1c) absorbers
with drastic change, that is natural in binary scenario but never been
seen in normal AGNs. Chandra turns out to be the only facility which
can further monitor the unprecedented target with high-quality spectra
in the next five months (from Feb. To June, visibility gap for
XMM-Newton). Hopefully Chandra will contribute significantly to
confirm the first SMBH binary merger event and explore high energy
physical process happening during the final stage of the binary
inspiral.
Title : Probing the X-rays from an unprecedented SMBH Binary at the Last
Inspiraling Stage
PI: Jiang
Abstract: We have recently discovered the first likely SMBH merger event ever
discovered in human history. The final merger will happen within three
years, maybe as short as three months. High-quality X-ray spectra
might be one of the most powerful electromagnetic signal to study the
last inspiraling stage. Our requested XMM-Newton ToO observations on
Dec.31 and Jan.19 have unveiled ultra-high velocity (>0.1c) absorbers
with drastic change, that is natural in binary scenario but never been
seen in normal AGNs. Chandra turns out to be the only facility which
can further monitor the unprecedented target with high-quality spectra
in the next five months (from Feb. To June, visibility gap for
XMM-Newton). Hopefully Chandra will contribute significantly to
confirm the first SMBH binary merger event and explore high energy
physical process happening during the final stage of the binary
inspiral.
Title : Probing the X-rays from an unprecedented SMBH Binary at the Last
Inspiraling Stage
PI: Jiang
Abstract: We have recently discovered the first likely SMBH merger event ever
discovered in human history. The final merger will happen within three
years, maybe as short as three months. High-quality X-ray spectra
might be one of the most powerful electromagnetic signal to study the
last inspiraling stage. Our requested XMM-Newton ToO observations on
Dec.31 and Jan.19 have unveiled ultra-high velocity (>0.1c) absorbers
with drastic change, that is natural in binary scenario but never been
seen in normal AGNs. Chandra turns out to be the only facility which
can further monitor the unprecedented target with high-quality spectra
in the next five months (from Feb. To June, visibility gap for
XMM-Newton). Hopefully Chandra will contribute significantly to
confirm the first SMBH binary merger event and explore high energy
physical process happening during the final stage of the binary
inspiral.
Title : Probing the X-rays from an unprecedented SMBH Binary at the Last
Inspiraling Stage
PI: Jiang
Abstract: We have recently discovered the first likely SMBH merger event ever
discovered in human history. The final merger will happen within three
years, maybe as short as three months. High-quality X-ray spectra
might be one of the most powerful electromagnetic signal to study the
last inspiraling stage. Our requested XMM-Newton ToO observations on
Dec.31 and Jan.19 have unveiled ultra-high velocity (>0.1c) absorbers
with drastic change, that is natural in binary scenario but never been
seen in normal AGNs. Chandra turns out to be the only facility which
can further monitor the unprecedented target with high-quality spectra
in the next five months (from Feb. To June, visibility gap for
XMM-Newton). Hopefully Chandra will contribute significantly to
confirm the first SMBH binary merger event and explore high energy
physical process happening during the final stage of the binary
inspiral.
Title : Probing the X-rays from an unprecedented SMBH Binary at the Last
Inspiraling Stage
PI: Jiang
Abstract: We have recently discovered the first likely SMBH merger event ever
discovered in human history. The final merger will happen within three
years, maybe as short as three months. High-quality X-ray spectra
might be one of the most powerful electromagnetic signal to study the
last inspiraling stage. Our requested XMM-Newton ToO observations on
Dec.31 and Jan.19 have unveiled ultra-high velocity (>0.1c) absorbers
with drastic change, that is natural in binary scenario but never been
seen in normal AGNs. Chandra turns out to be the only facility which
can further monitor the unprecedented target with high-quality spectra
in the next five months (from Feb. To June, visibility gap for
XMM-Newton). Hopefully Chandra will contribute significantly to
confirm the first SMBH binary merger event and explore high energy
physical process happening during the final stage of the binary
inspiral.
Title : Probing the X-rays from an unprecedented SMBH Binary at the Last
Inspiraling Stage
PI: Jiang
Abstract: We have recently discovered the first likely SMBH merger event ever
discovered in human history. The final merger will happen within three
years, maybe as short as three months. High-quality X-ray spectra
might be one of the most powerful electromagnetic signal to study the
last inspiraling stage. Our requested XMM-Newton ToO observations on
Dec.31 and Jan.19 have unveiled ultra-high velocity (>0.1c) absorbers
with drastic change, that is natural in binary scenario but never been
seen in normal AGNs. Chandra turns out to be the only facility which
can further monitor the unprecedented target with high-quality spectra
in the next five months (from Feb. To June, visibility gap for
XMM-Newton). Hopefully Chandra will contribute significantly to
confirm the first SMBH binary merger event and explore high energy
physical process happening during the final stage of the binary
inspiral.
Title : An Intermediate Mass Black Hole Candidate at the Centre of 47 Tuc
PI: Paduano
Abstract: We are currently in the middle of a large radio observing campaign
(406 hr) with the Australia Telescope Compact Array (ATCA) which will
produce the deepest radio image of the globular cluster 47 Tucanae to
identify faintly accreting black holes. Preliminary results from our
ongoing campaign based on data acquired in April/July/October 2021
have identified a radio counterpart to a previously identified faint
X-ray source. Its location at the photometric centre of the cluster
implies this object could be an intermediate mass black hole (IMBH)
candidate. As 47 Tucanae has not been observed by Chandra since 2015,
we request a 20 ks observation quasi-simultaneous with the last
segment of our ATCA observations to rule out the possibility of
enhanced radio/X-ray activity from an XRB. This will allow us to
assess the presence of an accreting IMBH in a globular cluster based
on direct evidence for the first time.
Title : Search for the X-ray counterpart to GLEAM-X J162759.5-523504.3
PI: Hurley-Walker
Abstract: During a Galactic Plane survey with the Murchison Widefield Array
(MWA), a peculiar periodic radio transient has been discovered
(Hurley-Walker et al. 2021, Nature in press; info under embargo) with
a periodicity of 1091.169(5) s, a very variable flux, going from
undetected to values as high as 20-50Jy during periods of radio
outburst, lasting a few months (two such periods were observed in
January and March 2018), with a 90% linear polarization, and a very
spiky and variable pulse profile. From a detailed timing analysis, a
dispersion measure of DM=57+/-1 pc cm^-3 was calculated (distance~1.3
kpc). We expect this to be a magnetar having witnessed a conspicuous
fall-back accretion at birth that slew down its spin period
substantially. A short Swift XRT observation of ~5ks could constrain
its X-ray luminosity to < 10^33 erg/s. If it is a magnetar the source
might have in quiescence, a luminosity of ~10^30 erg/s. Deeper X-ray
observations are needed to set meaningful constraints.
Title : Tracking the X-ray Emission of the Remarkable SGRB 211106A
PI: Rouco Escorial
Abstract: The distribution of jet angles for short gamma-ray bursts (SGRBs) is
critical to constrain as it directly affects the true energy scale and
event rate, which is of particular interest in the midst of the new
LVK run for next year. Our current knowledge of the jet angle
distribution comes almost exclusively from X-ray observations at >1
day after the burst. Here, we propose for a Chandra DDT observation to
continue to monitor the afterglow of SGRB 211106A and constrain its
late-time collimation up to ~60 days post-trigger, either from the
detection of the X-ray afterglow, which places a lower limit on the
opening angle at >15 deg, or a non-detection of the afterglow,
indicating a jet break has occurred and constraining the jet break to
20-25 deg. We have broad-band afterglow observations, which will be
leveraged to provide the tightest constraints on the jet angle.
Title : Tracking the X-ray Emission of the Remarkable SGRB 211106A
PI: Rouco Escorial
Abstract: The distribution of jet angles for short gamma-ray bursts (SGRBs) is
critical to constrain as it directly affects the true energy scale and
event rate, which is of particular interest in the midst of the new
LVK run for next year. Our current knowledge of the jet angle
distribution comes almost exclusively from X-ray observations at >1
day after the burst. Here, we propose for a Chandra DDT observation to
continue to monitor the afterglow of SGRB 211106A and constrain its
late-time collimation up to ~60 days post-trigger, either from the
detection of the X-ray afterglow, which places a lower limit on the
opening angle at >15 deg, or a non-detection of the afterglow,
indicating a jet break has occurred and constraining the jet break to
20-25 deg. We have broad-band afterglow observations, which will be
leveraged to provide the tightest constraints on the jet angle.
Title : The wide angle outflow of SGRB 210726A
PI: Schroeder
Abstract: The distribution of jet angles for short gamma-ray bursts (SGRBs) is
critical to constrain as it directly affects the true energy scale and
event rate. The event rate is of particular interest in the
gravitational wave era. Our current knowledge of the jet angle
distribution comes almost exclusively from X-ray observations at >1
day after the burst. Here, we propose for a Chandra TOO observation to
continue to monitor the afterglow of SGRB 210726A and constrain its
collimation, either from the detection of the X-ray afterglow, which
places a lower limit on the opening angle at >35 deg, or a
non-detection of the afterglow, indicating a jet break has occurred
and constraining the jet break to 13-35 deg. We have broad-band
afterglow observations, which will be leveraged to provide the
tightest constraints on the jet angle. This would be the first
detection of a cosmological SGRB afterglow at >50 days, complementing
the longest lasting detections of an SGRB radio afterglow.
Title : An Intermediate Mass Black Hole Candidate at the Centre of 47 Tuc
PI: Paduano
Abstract: We are currently in the middle of a large radio observing campaign
(406 hr) with the Australia Telescope Compact Array (ATCA) which will
produce the deepest radio image of the globular cluster 47 Tucanae to
identify faintly accreting black holes. Preliminary results from our
ongoing campaign based on data acquired in April/July/October 2021
have identified a radio counterpart to a previously identified faint
X-ray source. Its location at the photometric centre of the cluster
implies this object could be an intermediate mass black hole (IMBH)
candidate. As 47 Tucanae has not been observed by Chandra since 2015,
we request a 20 ks observation quasi-simultaneous with the last
segment of our ATCA observations to rule out the possibility of
enhanced radio/X-ray activity from an XRB. This will allow us to
assess the presence of an accreting IMBH in a globular cluster based
on direct evidence for the first time.
Title : Search for the X-ray counterpart to GLEAM-X J162759.5-523504.3
PI: Hurley-Walker
Abstract: During a Galactic Plane survey with the Murchison Widefield Array
(MWA), a peculiar periodic radio transient has been discovered
(Hurley-Walker et al. 2021, Nature in press; info under embargo) with
a periodicity of 1091.169(5) s, a very variable flux, going from
undetected to values as high as 20-50Jy during periods of radio
outburst, lasting a few months (two such periods were observed in
January and March 2018), with a 90% linear polarization, and a very
spiky and variable pulse profile. From a detailed timing analysis, a
dispersion measure of DM=57+/-1 pc cm^-3 was calculated (distance~1.3
kpc). We expect this to be a magnetar having witnessed a conspicuous
fall-back accretion at birth that slew down its spin period
substantially. A short Swift XRT observation of ~5ks could constrain
its X-ray luminosity to < 10^33 erg/s. If it is a magnetar the source
might have in quiescence, a luminosity of ~10^30 erg/s. Deeper X-ray
observations are needed to set meaningful constraints.
Title : Ejecta Collimation and True Energetics of GRB210905A at z=6.318
PI: MARGUTTI
Abstract: We propose deep Chandra observations of GRB210905A at z=6.318 to
solidly locate the afterglow jet break time, and hence constrain the
ejecta collimation and true energetic of a GRB belonging to the rare
class of z>6 burst
Title : Was the TDE candidate eRASSt J0936 produced by a wandering SMBH?
PI: Malyali
Abstract: On 2021-05-13, eROSITA detected a new TDE candidate, characterised by
an ultra-soft (kT~70 eV) X-ray spectrum and associated with a recently
quiescent FRII galaxy at z=0.12 (eRASSt J0936; see ATel#14668).
Follow-up Swift observations since the eROSITA detection revealed a
declining X-ray flux, with no significant X-ray spectral change (i.e.
remains ultra-soft); the latest observed 0.2-2 keV flux was
(5+/-3)e-14 erg/s/cm2 on 2021-10-06.
The implied SMBH mass from the M-sigma relation for this galaxy is
log(Mbh/Msun)~8.8, which exceeds the Hills mass for tidal disruption
of a MS star by a non-spinning SMBH. Recent work suggests a
significant fraction of TDEs may be produced by wandering SMBHs that
lie off-nuclear in their host (Fig. 2 of Ricarte+ in arXiv
2107.02132)- this may explain why we see a TDE candidate in a galaxy
with log(Mbh/Msun)~8.8. We request a 30ks observation of J0936 with
HRC-I to constrain the location of J0936 to within ~1.1 kpc (0.5; 3
sig.) of the host's centre.
Title : Determining the Mass of the IC 10 X-1 Black Hole with Coordinated
Multiwavelength Observations
PI: Binder
Abstract: We request a 30 ks DDT Chandra/ACIS-S observation of the black hole
(BH) + Wolf-Rayet (WR) binary IC 10 X-1 to complement approved
Hubble/COS FUV spectroscopy and Swift/XRT+UVOT monitoring between 9-22
Nov 2021. The Chandra observation will allow us to determine the
orbital phases at which the Hubble and Swift observations are obtained
to high precision, model the X-ray spectrum and radiation field in
which the FUV lines form, and constrain the period derivative Pdot of
the system.
Title : VLA+Chandra Observations of Ic-BL Supernovae with ZTF High-Cadence
Light Curves
PI: Ho
Abstract: Broad-lined Ic supernovae (Ic-BL) are a subclass of stripped-envelope
core-collapse supernovae notable for their high energies, high
velocities, and association with long-duration gamma-ray bursts
(GRBs). After decades of follow-up efforts, it remains unknown why
most Ic-BL SNe lack a detected GRB. Nearby (z<0.065) Ic-BL SNe
associated with low-luminosity GRBs (LLGRBs) may represent the answer:
LLGRB-SNe have been argued to be jets viewed off-axis, jets choked
inside the stellar envelope or circumstellar material, or successful
jets that are less powerful than classical GRBs. Here we propose
observations of ZTF21acekmmm to test a novel approach, based on the
fact that nearby LLGRB-SNe exhibit an early (<1d) flash of optical
light that can be routinely resolved by high-cadence optical surveys
like the Zwicky Transient Facility.
Title : HIGH RESOLUTION STUDIES OF EXO 2030+375 DURING THE PEAK AND DECLINE OF
ITS RARE GIANT OUTBURST
PI: Pradhan
Abstract: As of Sep 10, EXO 2030+375 is rising in BAT indicative of the onset of
giant erratic Type II outburst seen only twice in the source since
discovery. We take this rare opportunity to study high-res
characteristics of the source near outburst peak and during its
decline for 10 ks and 20 ks respectively. We will probe accretion
near Eddington luminosity and disk winds through the study of the
X-ray continuum, emission lines and high velocity outflows. Since the
luminosity at giant outbursts are also thought to be accompanied by
such high velocity out seen in a few Be X-ray binaries so far, we
expect to find the outflows in EXO 2030+375. We will also: look for
variability of fluorescence lines originating in accretion disk and
place constraints on the Alfven radius to provide a magnetic field
estimate of the neutron star in the system and investigate the
scattering halos by studying the differences between the source and
halo light curves.
Title : A luminous kilonova or a faint supernova? The curious case of
GRB210704A
PI: Troja
Abstract: GRB210704A is a GRB of intermediate duration (T90~4 s) whose
progenitor remains uncertain. Its location in a nearby galaxy's
cluster as well as the lack of any on-going star formation support an
old progenitor system, such as a compact binary merger. However, its
duration and bright long-lived afterglow are more typical of a long
duration burst. Its hybrid properties may also point to an exotic
channel of formation, such as as the merger of a white dwarf/black
hole system. We request a Chandra observation to track the evolution
of its non-thermal emission to late times, when the source has faded
below the Swift XRT detection threshold. These observations are
critical to characterize the standard afterglow, identify any excess
emission, and ultimately understand the nature of the shallow
optical/nIR decay which is a direct clue to the GRB progenitor
system.
Title : Dissecting the Supersoft Source Phase of the Magnetic Nova V1674 Her
(Nova Her 2021)
PI: Drake
Abstract: V1674 Her (Nova Her 2021) is the first bright nova supersoft source
that has been identified with a magnetic white dwarf progenitor. An
8.357 minute period was found in ZTF data taken between 2018 and 2021
that is most likely caused by the spin period of the WD, strongly
indicating an intermediate polar. The presence of strong neon emission
lines in spectra from 2021 June 30 also demonstrate that V1674 Her is
a member of the class of neon novae. It has become a very bright
supersoft X-ray source with a Swift XRT count rate of 10 count/s. A
Chandra LETG+HRC-S spectrum should be uncomplicated by accretion and
can be phase-folded with the known period. It will provide a powerful
test of whether or not nuclear burning is insensitive to the local
magnetic field, and reveal velocity signatures of radiatively-driven
outflow collimation. V1674 Her is the first bright SSS to be so
characterized prior to outburst.
Title : Searching for pulsations in a magnetic CV's nova
PI: Maccarone
Abstract: The bright, fast nova TCP J18573095+1653396 has shown an 8.4 minute
period in ZTF data that were taken before the nova explosion. This
period makes sense as a magnetized white dwarf's spin period. This
creates the potential for determining if the supersoft phases of these
systems show the spin oscillations of the white dwarfs. The period is
an awkward one for being reliably detected by satellites with
low-Earth orbits, so a short Chandra observation is requested.
Title : HETG Spectroscopy of the Black Hole 4U 1543-475
PI: Miller
Abstract: 4U 1543-475 is a recurrent black hole X-ray binary. It is one of the
few sources with a dynamically confirmed mass, and measured distance
(M = 9.4 +/- 2.0 Msun, distance = 7.5 +/- 1.0 kpc; Park et al. 2004).
This means that it is a rare case wherein black hole spin can be
measured using continuum fitting. The source has risen very quickly
from the detection of renewed activity only (up to 2.5-3 Crab in just
2-3 days, see ATEL 14701). It is now in the soft state, which is the
one wherein spin can be measured as other contributions to the
continuum are minimal. In this state, disk winds and UFOs can also be
detected using the HETGS. With the ACIS-S array in CC mode, Chandra
is uniquely able to observe a source this bright without distortions.
Title : Chandra Observation of AT2020mrf: the Most X-ray Luminous AT2018cow
Analog
PI: Yao
Abstract: The past several years has shown that the landscape of massive-star
death is unexpectedly rich and diverse. The (heterogeneous) class of
``fast blue optical transients'' (FBOT) has now established that a
large fraction of massive stars undergo significant mass losses, and
in some cases these losses serve as omens of their deaths
(supernovae). The discovery of AT2018cow (z=0.0141) established a
genuinely new type of cosmic explosion. AT2018cow was not only an FBOT
but was marked by intense X-ray emission and variability which
requires a powerful long-lived engine. Its high radio luminosity and
late millimeter peak implied dense circum-stellar medium (CSM).
Following the discovery of AT2018cow two events, ZTF18abvkwla
(z=0.271), CSS161010 (z=0.034; archival analysis), and AT2020xnd
(z=0.244) were identified. A fundamental open question is the nature
of the central engine. The X-ray band is essential since it probes
materials closest to the central power source.
Title : Probing the disc-wind-jet connection in black hole transients
PI: Diaz Trigo
Abstract: We request three 50 ks observations of the candidate black hole
low-mass X-ray binary MAXI J1803-298 during the hard-to-soft state
transition with Chandra/HETGS to investigate the presence of narrow
X-ray absorption/emission features in the spectra, which are a
signature of a disc wind, and their relation to the accreting regime.
Such features, identified with ions like Fe XXV and Fe XXVI give us
information about the mass outflow rate and the launching mechanism of
the wind. With coordinated radio observations we will probe the
relationship between jet power and wind properties and how the radio
flux density correlates with the X-ray flux in different accretion
regimes.
Title : Chandra grating observations of a newly launched outflow from a
supermassive black hole during an outburst
PI: Pasham
Abstract: We are requesting for a 50ks Chandra/LETG exposure of the nuclear
transient AT2019avd following NICER discovery of an outflow. LETG data
would provide a detailed view of this newly launched outflow as the
supermassive black hole (SMBH) is currently transitioning from an
X-ray soft to an X-ray hard state. This is analogous to a high/soft to
low/hard state transition in X-ray binaries which is often accompanied
by outflows. NICER has been monitoring AT2019avd at an unprecedented
cadence of once to several visits per day since its first public X-ray
detection on 19 Sept 2020. The proposed Chandra data will be part of
the legacy dataset to study accretion state transitions in SMBHs and
will guide future observations of SMBH outbursts with the upcoming
XRISM mission. This state transition and outflow could not have been
predicted at the time Chandra GO proposals were due and this
opportunity will not be available until the next GO cycle as the
source is already declining in flux.
Title : Chandra grating observations of a newly launched outflow from a
supermassive black hole during an outburst
PI: Pasham
Abstract: We are requesting for a 50ks Chandra/LETG exposure of the nuclear
transient AT2019avd following NICER discovery of an outflow. LETG data
would provide a detailed view of this newly launched outflow as the
supermassive black hole (SMBH) is currently transitioning from an
X-ray soft to an X-ray hard state. This is analogous to a high/soft to
low/hard state transition in X-ray binaries which is often accompanied
by outflows. NICER has been monitoring AT2019avd at an unprecedented
cadence of once to several visits per day since its first public X-ray
detection on 19 Sept 2020. The proposed Chandra data will be part of
the legacy dataset to study accretion state transitions in SMBHs and
will guide future observations of SMBH outbursts with the upcoming
XRISM mission. This state transition and outflow could not have been
predicted at the time Chandra GO proposals were due and this
opportunity will not be available until the next GO cycle as the
source is already declining in flux.
Title : The disk/jet connection of a black hole in quiescence
PI: Carotenuto
Abstract: Black hole X-ray binaries display a correlation between the radio
luminosity originating from the relativistic jets, and the X-ray
luminosity, linked to the inner accretion flow. Some outlier (hybrid)
sources display a correlation that varies with the accretion rate, and
their behaviour in quiescence is still unknown. The path of a source
on the radio/X-ray diagram can be used to test models of accretion
flows and jets emission mechanisms. The new BH MAXI J1348-630 has been
densely monitored during its 2019/2020 outburst and is, so far, the
hybrid source with the best coverage, but its quiescence level has not
been constrained yet. We propose a single DDT Chandra observation (30
ks), that will be coupled to a deep radio observation (24h with ATCA)
in July 2021 (already scheduled), which will allow us to detect an
hybrid source in quiescence and therefore constrain its full path
along the radio/X-ray diagram from outburst down to quiescence.
Title : Chandra Observation of AT2020mrf: the Most X-ray Luminous AT2018cow
Analog
PI: Yao
Abstract: The past several years has shown that the landscape of massive-star
death is unexpectedly rich and diverse. The (heterogeneous) class of
``fast blue optical transients'' (FBOT) has now established that a
large fraction of massive stars undergo significant mass losses, and
in some cases these losses serve as omens of their deaths
(supernovae). The discovery of AT2018cow (z=0.0141) established a
genuinely new type of cosmic explosion. AT2018cow was not only an FBOT
but was marked by intense X-ray emission and variability which
requires a powerful long-lived engine. Its high radio luminosity and
late millimeter peak implied dense circum-stellar medium (CSM).
Following the discovery of AT2018cow two events, ZTF18abvkwla
(z=0.271), CSS161010 (z=0.034; archival analysis), and AT2020xnd
(z=0.244) were identified. A fundamental open question is the nature
of the central engine. The X-ray band is essential since it probes
materials closest to the central power source.
Title : Search for jet afterglow from a magnetar-powered X-ray transient
PI: Lin
Abstract: Chandra just serendipitously detected a fast X-ray transient on 2021
April 23. It has a special X-ray light curve of a fast rise to a
plateau lasting a few thousand seconds, followed by a steep decay,
very similar to CDF-S XT2, which was recently shown to be powered by a
magnetar formed in a binary neutron star (BNS) merger. Such a unique
signal, if confirmed, can be synthesized with gravitational wave to
probe BNS mergers and dense
matter. We request a 60 ks Chandra observation to be carried out in
one month to search for a delayed off-axis jet afterglow in order to
confirm its BNS merger nature.
Title : Probing the disc-wind-jet connection in black hole transients
PI: Diaz Trigo
Abstract: We request three 50 ks observations of the candidate black hole
low-mass X-ray binary MAXI J1803-298 during the hard-to-soft state
transition with Chandra/HETGS to investigate the presence of narrow
X-ray absorption/emission features in the spectra, which are a
signature of a disc wind, and their relation to the accreting regime.
Such features, identified with ions like Fe XXV and Fe XXVI give us
information about the mass outflow rate and the launching mechanism of
the wind. With coordinated radio observations we will probe the
relationship between jet power and wind properties and how the radio
flux density correlates with the X-ray flux in different accretion
regimes.
Title : Probing the disc-wind-jet connection in black hole transients
PI: Diaz Trigo
Abstract: We request three 50 ks observations of the candidate black hole
low-mass X-ray binary MAXI J1803-298 during the hard-to-soft state
transition with Chandra/HETGS to investigate the presence of narrow
X-ray absorption/emission features in the spectra, which are a
signature of a disc wind, and their relation to the accreting regime.
Such features, identified with ions like Fe XXV and Fe XXVI give us
information about the mass outflow rate and the launching mechanism of
the wind. With coordinated radio observations we will probe the
relationship between jet power and wind properties and how the radio
flux density correlates with the X-ray flux in different accretion
regimes.
Title : Probing the disc-wind-jet connection in black hole transients
PI: Diaz Trigo
Abstract: We request three 50 ks observations of the candidate black hole
low-mass X-ray binary MAXI J1803-298 during the hard-to-soft state
transition with Chandra/HETGS to investigate the presence of narrow
X-ray absorption/emission features in the spectra, which are a
signature of a disc wind, and their relation to the accreting regime.
Such features, identified with ions like Fe XXV and Fe XXVI give us
information about the mass outflow rate and the launching mechanism of
the wind. With coordinated radio observations we will probe the
relationship between jet power and wind properties and how the radio
flux density correlates with the X-ray flux in different accretion
regimes.
Title : A look at NGC 4151 at an exceptional flux and hardness
PI: Miller
Abstract: As of April 22, NGC 4151 is the brightest that it has been in the
Swift BAT, and today's Swift XRT snapshot records a flux 20% higher
than prior high-flux states (that are typically associated with low
BAT fluxes). Further proof of a rare accretion state and accretion
flow can be gleaned from ZTF monitoring, which finds NGC 4151 at its
brightest point for the entire monitoring period. The sensitivity and
resolution of the HETG is ideal for studying the narrow Fe K line and
disk winds. In prior published results, we showed that this line is
likely asymmetric and may arise at radii smaller than the BLR, rather
than within the BLR or torus. Whereas the equivalent width of this
line is 180 eV in prior Chandra spectra of hard states, and <100 eV in
soft states, the latest XRT snapshot suggests an equivalent width of
500-700 eV. This presents a remarkable opportunity to study the
accretion flow in this key source. We request a 50 ks obs.,
commensurate with the longest observing window.
Title : Unraveling the nature of the persistent radio source associated to
FRB201124A with Chandra
PI: Piro
Abstract: FRB201124A is the second repeating fast radio burst (FRB) in which a
persistent radio source (PRS) has been very recently detected. Due to
its its closer distance (z=0.098), observations of the field of
FRB201124A can provide further insights into the nature of PRSs
associated to FRBs. Recently, multiple FRBs were detected from
FRB201124A by ASKAP, uGMRT, and the VLA. Following this, we performed
observations with the VLA and Swift/XRT. In our VLA observation, we
detect a PRS consistent with the locations reported for the VLA FRBs,
uGMRT FRBs, and uGMRT persistent radio source. Using the spectral
energy distribution for the persistent source, we determine that the
unique sensitivity of Chandra will allow us to detect the source with
high significance. This will yield a subarcsec location accuracy and a
solid association with the PRS allowing us to determine the offset of
the PRS from its galaxy and the FRB. We hereby request a 30 ks DDT
observation with Chandra to accomplish this goal.
Title : CHANDRA DDT observation of the nuclear transient -
ASASSN-20hx/AT2020ohl
PI: Mandal
Abstract: ASASSN-20hx/AT2020ohl was discovered in the nearby (z=0.0167) X-ray
and radio faint, galaxy NGC 6297. The post-discovery Swift follow-up
for more than 200 days showed that the object is bright in X-ray, NUV,
with persistently bluish nature consistent with canonical TDEs,
although unlike TDEs this object has not shown any line formation in
the optical spectrum over this long duration. To identify the nature
of the source we have triggered Jansky Very Large Array (JVLA) in
X-Band (proposal ID: VLA/20B-427), and detected the high-frequency
radio counterpart at the center of the galaxy as well as another radio
source very near (~1.5'') to the center. We are now motivated to
observe the field using CHANDRA/HRC-I to find out the X-ray
association with one of these two radio-knots. Noteworthy, this field
was never imaged from CHANDRA. Here we propose for one epoch
CHANDRA/HRC-I ToO observation of the field of AT2020ohl in the highest
spatial resolution.
Title : An accurate position of a new nearby ULX in NGC 4945
PI: Brightman
Abstract: On February 8th, we discovered a new ULX in the galaxy NGC 4945
(http://www.astronomerstelegram.org/?read=14380). The new ULX was
detected serendipitously in a Swift/XRT observation of the galaxy, and
no X-ray source has been reported at or near this position before
despite numerous previous Swift, Chandra, XMM-Newton, and NuSTAR
observations. We have continued to follow the source with Swift,
finding that the source continues to be active, and here we request to
follow up with a Chandra observation. The Chandra data will provide an
accurate position of the source, which will in turn allow a search for
a potential optical counterpart. We already have a candidate
counterpart in the 2.7" Swift positional error circle, but Chandra is
needed to confirm this. We request a 10-ks exposure, which is required
to detect enough X-ray sources in the field of view to carry out the
astrometric correction.
Title : A Highly-Polarized, Highly-Variable Radio Source Near the Galactic
Center: A New Magnetar or Transitional MSP?
PI: Kaplan
Abstract: A highly variable radio source was discovered by ASKAP about 4 degrees
from the Galactic Center (GC) at a latitude of -0.03. Bright,
polarized emission was recently detected with MeerKAT but with large
flux variations on timescales of hours/days. The location of the
source within the plane and close to the GC along with the radio
variability/polarization point to a pulsar nature for this intriguing
object. The source might be a radio-loud magnetar or a transitional
millisecond pulsar (tMSP). In the case of a magnetar the radio
emission is always observed in connection with an X-ray outburst. If
this source is a tMSP it should be now in its ?intermediate? or
?pulsar'' state, again with predicted X-ray emission. In either
interpretation the source would be very interesting: either would be a
rare source, and both would allow important constraints on the pulsar
progenitors and population in that region.
Title : Afterglow identification for short GRB 190610A
PI: Tohuvavohu
Abstract: GRB 190610A is a short hard burst discovered and localized by
Swift/BAT. The BAT localization is consistent with a nearby galaxy at
~165 Mpc. XRT follow-up observations yielded an afterglow candidate,
below existing upper limits. Due to the source's faintness a
determination of fading and the confident afterglow identification to
distinguish this from a possible contaminating background source
cannot be made with XRT. We request a late-time Chandra observation of
this XRT afterglow candidate, to help determine whether this burst is
a member of an extremely rare class of local, nearly on-axis, neutron
star mergers within the GW detector horizon.
Title : Resolving the Flaring Site of PKS 1127-145 jet
PI: Siemiginowska
Abstract: On December 11, 2020 the Fermi-LAT Collaboration reported a strong
gamma-ray flare associated with the flat spectrum radio loud quasar
PKS 1127-145 at redshift z=1.184. This is the first strong gamma-ray
flaring activity observed from this source in the Fermi era with the
highest gamma-ray flux ever detected in this quasar, a factor of 50
higher than the average flux estimated in the 4FGL catalogue. This is
the first opportunity for Chandra to observe this quasar in an active
state. The Chandra observation will provide the required arcsec
resolution to confirm that the gamma-ray flare is associated with this
quasar and to locate the site of the flare.
Title : GRB201214B: an off-axis burst in the nearby universe?
PI: Troja
Abstract: GRB201214B is a weak gamma-ray burst discovered by Fermi GBM and
localized by Swift BAT close to a nearby galaxy at D~280 Mpc. XRT
follow-up observations do not identify any counterpart within the BAT
error region, showing that this event is not associated with a bright
X-ray afterglow. Its weak gamma-ray signal, lack of early X-ray
emission and possible association with a nearby galaxy are reminiscent
of GRB150101B and GW170817, two off-axis afterglows detected by
Chandra. If GRB201214B is a similar explosion seen off-axis, its
afterglow would slowly rise and peak several days/weeks after the GRB.
We therefore request a pair of Chandra observations to search for the
onset of a delayed X-ray afterglow, and test whether this GRB heralds
a rare neutron star merger in the nearby universe.
Title : GRB201214B: an off-axis burst in the nearby universe?
PI: Troja
Abstract: GRB201214B is a weak gamma-ray burst discovered by Fermi GBM and
localized by Swift BAT close to a nearby galaxy at D~280 Mpc. XRT
follow-up observations do not identify any counterpart within the BAT
error region, showing that this event is not associated with a bright
X-ray afterglow. Its weak gamma-ray signal, lack of early X-ray
emission and possible association with a nearby galaxy are reminiscent
of GRB150101B and GW170817, two off-axis afterglows detected by
Chandra. If GRB201214B is a similar explosion seen off-axis, its
afterglow would slowly rise and peak several days/weeks after the GRB.
We therefore request a pair of Chandra observations to search for the
onset of a delayed X-ray afterglow, and test whether this GRB heralds
a rare neutron star merger in the nearby universe.
Title : The recurring rebrightening of ESO253-G003
PI: Payne
Abstract: We discovered highly atypical flares within the AGN ESO253-G003 that
are periodic with a non-zero negative period derivative (Payne et al.
2020). These outburst events have occurred predictably for the last
six years. Numerous rebrightening events are highly unusual for an
AGN, which normally vary at a low-level following a damped random walk
model. The precise origin of these flares remains unknown but they
could be caused by a repeating partial tidal disruption event (TDE).
Studying this object will provide new and distinctive insights into
the mechanisms driving this transient and the broader inner workings
of AGN variability.
Title : The recurring rebrightening of ESO253-G003
PI: Payne
Abstract: We discovered highly atypical flares within the AGN ESO253-G003 that
are periodic with a non-zero negative period derivative (Payne et al.
2020). These outburst events have occurred predictably for the last
six years. Numerous rebrightening events are highly unusual for an
AGN, which normally vary at a low-level following a damped random walk
model. The precise origin of these flares remains unknown but they
could be caused by a repeating partial tidal disruption event (TDE).
Studying this object will provide new and distinctive insights into
the mechanisms driving this transient and the broader inner workings
of AGN variability.
Title : On the shoulders of Gas Giants: Observing Saturn's X-rays with a
varying external driver
PI: Weigt
Abstract: In November 2020, the planets Jupiter and Saturn will be in unique
alignment: Saturn will be immersed in Jupiter's magnetotail. This only
occurs once in every 19 years and is unique to the gas giants. Voyager
2 ~40 years ago found the environment at Saturn during this time was a
variable parameter space and found the (magneto-)tail of Jupiter to
flap, without any coincident remote sensing or X-ray data. This caused
Saturn to be alternately every 2-3 days immersed in the rarefied tail
and then denser solar wind. These changes are likely to produce shocks
as the magnetosphere compresses and expands in response to changing
pressure and dynamics, brightening the aurora. However, there are
still many unknowns about how Saturn's auroral/disk emissions will
respond to no solar wind drivers.
Therefore, we propose to observe Saturn?s X-rays in this unique
unknown parameter space for the first time. The data provided will aid
the ongoing multiwavelength campaign, exploring Saturn's response.
Title : On the shoulders of Gas Giants: Observing Saturn's X-rays with a
varying external driver
PI: Weigt
Abstract: In November 2020, the planets Jupiter and Saturn will be in unique
alignment: Saturn will be immersed in Jupiter's magnetotail. This only
occurs once in every 19 years and is unique to the gas giants. Voyager
2 ~40 years ago found the environment at Saturn during this time was a
variable parameter space and found the (magneto-)tail of Jupiter to
flap, without any coincident remote sensing or X-ray data. This caused
Saturn to be alternately every 2-3 days immersed in the rarefied tail
and then denser solar wind. These changes are likely to produce shocks
as the magnetosphere compresses and expands in response to changing
pressure and dynamics, brightening the aurora. However, there are
still many unknowns about how Saturn's auroral/disk emissions will
respond to no solar wind drivers.
Therefore, we propose to observe Saturn?s X-rays in this unique
unknown parameter space for the first time. The data provided will aid
the ongoing multiwavelength campaign, exploring Saturn's response.
Title : On the shoulders of Gas Giants: Observing Saturn's X-rays with a
varying external driver
PI: Weigt
Abstract: In November 2020, the planets Jupiter and Saturn will be in unique
alignment: Saturn will be immersed in Jupiter's magnetotail. This only
occurs once in every 19 years and is unique to the gas giants. Voyager
2 ~40 years ago found the environment at Saturn during this time was a
variable parameter space and found the (magneto-)tail of Jupiter to
flap, without any coincident remote sensing or X-ray data. This caused
Saturn to be alternately every 2-3 days immersed in the rarefied tail
and then denser solar wind. These changes are likely to produce shocks
as the magnetosphere compresses and expands in response to changing
pressure and dynamics, brightening the aurora. However, there are
still many unknowns about how Saturn's auroral/disk emissions will
respond to no solar wind drivers.
Therefore, we propose to observe Saturn?s X-rays in this unique
unknown parameter space for the first time. The data provided will aid
the ongoing multiwavelength campaign, exploring Saturn's response.
Title : CHANDRA OBSERVATIONS OF A NEW SGR 1830-0645
PI: Kouveliotou
Abstract: Swift/BAT has discovered a magnetar-like soft (<50 keV) X-ray burst
(duration <0.1s) potentially from as new magnetar source, SGR
1830-0645 (GCN 28594). We would like to request a 10ks DDT observation
of this new source with HRC to determine an accurate position and
timing of its persistent emission. We intend, thereafter, to follow up
the source with XMM-Newton, and further determine its spectral and
timing properties. The magnetar population in our Galaxy is very small
(~30 sources) - this discovery will significantly, therefore,
increase this population and needs to be well studied. Further, the
source resides in a very dense area of the Galactic Plane (which
already hosts several magnetars) and HRC is the only instrument that
can locate it with great accuracy, so that we can have radio and
optical followup observations.
Title : Resolving RXJ1756 with Chandra: A Recoiling Black Hole Candidate or
Possible Triple AGN
PI: Koss
Abstract: The coalescence of binary supermassive black holes in galaxy mergers
is thought to constitute the strongest source of gravitational waves.
Theory suggests these waves carry momentum causing the merged SMBH to
experience a velocity recoil or kick that displaces or may even eject
it from the center of its host galaxy. Despite their importance, only
a few spatially or kinematically offset recoiling BH candidates are
known, and none has been confirmed with extensive multiwavelength
observing. We request DDT time to follow-up a very recent 2020 Aug 2
HST, XMM-Newton, and NuSTAR
observations of an extremely puzzling source RXJ1756.4+5235, a
recoiling supermassive black hole candidate or possible triple AGN.
Title : A dramatic change in an agn
PI: Miller
Abstract: A full science justification has been sent to the director in a
separate email.
Title : A dramatic change in an agn
PI: Miller
Abstract: A full science justification has been sent to the director in a
separate email.
Title : A dramatic change in an agn
PI: Miller
Abstract: A full science justification has been sent to the director in a
separate email.
Title : A dramatic change in an agn
PI: Miller
Abstract: A full science justification has been sent to the director in a
separate email.
Title : Chandra observation of the mysterious X-ray transient AT2019wey/SRG
PI: Kulkarni
Abstract: AT2019wey/SRG though discovered in December 2019 only rose to
prominence with the discovery of strong X-ray emission by the
Spectrum-Roentgen-Gamma (SRG) mission in March, 2020. The source was
not present in any historical optical sky surveys nor Rosat All Sky
survey, though it was detected at 17.5 mag and few mCrab just from
this year. The unusual nature of this Galactic source (various H and
He lines at z=0) led to generous allocation of Swift, NICER, and
NuSTAR monitoring time. The detection of relativistic reflection from
NuSTAR and the detection of radio emission from VLA, taken together,
suggest that the source is likely an accreting stellar black hole.
The long 'on state' is unprecedented for a low mass accreting black
hole binary.
We propose a Chandra HETG exploratory observation to detect possible
narrow line iron components and also spectrally resolve the low
energy (<1 keV) hump. These may provide new insights into the nature
of this mysterious transient.
Title : Follow up a special hard tidal disruption event
PI: Lin
Abstract: We just discover a remarkable UV/X-ray outburst from Swift in our
archival data search. Because it is positionally coincident with the
nucleus of a nearby inactive galaxy at z=0.026, it is a strong tidal
disruption event (TDE) candidate. It is remarkable in three aspects:
(1) a well covered UV/X-ray light curve constraining the outburst
start time to within two weeks; (2) hard X-ray spectra (powerlaw
photon index 1.8-2.5) seen in only a few TDEs; (3) a surprising fast
rebrightening (by one order of magnitude and last for one month) in
X-rays but not in the UV during the overall decay. We now request a
Chandra observation to confirm the nuclear origin of the event, to
confirm the hardening of the X-ray spectra, as part of our long-term
campaign, to constrain the long-tern evolution of the X-ray emission.
Title : Chandra observations of PSR J1846-0258 in outburst
PI: Blumer
Abstract: PSR J1846-0258 (J1846), powering a bright and compact pulsar wind
nebula (PWN) in the young supernova remnant Kes 75, was the first
high-magnetic (B) field pulsar to display a magnetar-like behavior in
2006, blurring the distinction between rotation-powered pulsars and
magnetars. Chandra observations of J1846 performed 7 days past the
outburst activity revealed that the pulsar brightened (by a factor of
6 times) and its spectrum softened significantly such that it became
reminiscent of those observed from magnetars. Subsequent observations
in 2009 revealed that the pulsar had gone back to quiescence. J1846
has entered into a new state of activity on 1 Aug 2020, emitting a
short burst detected with Swift. We request a prompt follow up
observation with Chandra to study its magnetar-like behavior in
comparison with the 2006 bursts, and to search for any PWN variability
associated with the burst.
Title : Investigating the vertical structure of the disc wind in Her X-1
PI: Kosec
Abstract: Hercules X-1 is a unique neutron star X-ray binary system showing a
periodically precessing warped accretion disc. At the same time, it
exhibits a varying accretion disc wind. The variations are likely
driven by the disc precession and correspond to our observations
sampling different lines of sight above the warped disc, thus allowing
us to study the vertical disc wind structure. Our coordinated
XMM-Newton, NuSTAR and INTEGRAL campaign will observe a large part of
a single precession cycle of Her X-1, finely sampling the wind
structure, accurately measuring its total mass outflow rate and
shedding light on its launching mechanism. A simultaneous Chandra HETG
observation would greatly complement this dataset. It could fill-in
one of the XMM orbital gaps, expanding our time-resolved wind
parameter study. Additionally, it would allow us to cross-check the
wind parameters derived from XMM data, and to perform a full chemical
abundance study of the disc wind.
Title : Investigating the vertical structure of the disc wind in Her X-1
PI: Kosec
Abstract: Hercules X-1 is a unique neutron star X-ray binary system showing a
periodically precessing warped accretion disc. At the same time, it
exhibits a varying accretion disc wind. The variations are likely
driven by the disc precession and correspond to our observations
sampling different lines of sight above the warped disc, thus allowing
us to study the vertical disc wind structure. Our coordinated
XMM-Newton, NuSTAR and INTEGRAL campaign will observe a large part of
a single precession cycle of Her X-1, finely sampling the wind
structure, accurately measuring its total mass outflow rate and
shedding light on its launching mechanism. A simultaneous Chandra HETG
observation would greatly complement this dataset. It could fill-in
one of the XMM orbital gaps, expanding our time-resolved wind
parameter study. Additionally, it would allow us to cross-check the
wind parameters derived from XMM data, and to perform a full chemical
abundance study of the disc wind.
Title : X-ray observations of a candidate Pulsar Wind Nebula
PI: MARGUTTI
Abstract: We propose to re-observe the energetic SN2012au with Chandra. SN2012au
showed evidence for a remarkable radio re brightening (accompanied by
a radio spectrum inversion at GHz frequencies). Here we ask for deep
X-ray observations of SN2012au to constrain the high-energy part of
the spectrum and constrain the physical parameters.
Title : X-ray observations of a candidate Pulsar Wind Nebula
PI: MARGUTTI
Abstract: We propose to re-observe the energetic SN2012au with Chandra. SN2012au
showed evidence for a remarkable radio re brightening (accompanied by
a radio spectrum inversion at GHz frequencies). Here we ask for deep
X-ray observations of SN2012au to constrain the high-energy part of
the spectrum and constrain the physical parameters.
Title : X-ray Progenitor Constraints of the Subluminous Type Ia SN2020nlb
PI: Sand
Abstract: SN2020nlb is a newly discovered subluminous type Ia SN in the nearby
galaxy M85 (D~15 Mpc), found within two days of explosion. While it
is accepted that SNe Ia are the thermonuclear explosions of CO white
dwarfs, it is still unclear by what mechanisms the white dwarf gains
the necessary mass and how it then explodes. Deep X-ray observations
provide critical information on SN Ia progenitors as a probe of the
circumstellar material they left behind. SN2020nlb would represent
the first subluminous SN Ia with deep CSM limits in the X-ray, and may
lead to the first definitive detection!
Title : X-ray Progenitor Constraints of the Subluminous Type Ia SN2020nlb
PI: Sand
Abstract: SN2020nlb is a newly discovered subluminous type Ia SN in the nearby
galaxy M85 (D~15 Mpc), found within two days of explosion. While it
is accepted that SNe Ia are the thermonuclear explosions of CO white
dwarfs, it is still unclear by what mechanisms the white dwarf gains
the necessary mass and how it then explodes. Deep X-ray observations
provide critical information on SN Ia progenitors as a probe of the
circumstellar material they left behind. SN2020nlb would represent
the first subluminous SN Ia with deep CSM limits in the X-ray, and may
lead to the first definitive detection!
Title : INVESTIGATION ON MRK 335 IN AN INTERMEDIATE STATE
PI: Boissay-Malaquin
Abstract: We propose a DDT observation of the highly variable Narrow-Line
Seyfert 1 Mrk 335 with Chandra/HETG (150 ks DDT + 90 ks GTO). Because
of a pending observation accepted for cycle 5, NuSTAR will join such
Chandra observation on a best effort basis. We also seek to obtain a
contemporaneous NICER DDT observation. We aim to characterize the warm
absorbers previously detected in XMM-Newton/RGS data. We aim to
observe Mrk 335 in the next 10-20 days, while it has an intermediate
flux, ideal state for the detection of the absorbers. Observing now
ensures that we will catch the adequate intermediate state (according
to the Swift monitoring), but also offers a unique view of an AGN when
it is turning on again, after being in a low flux state for the past 2
years. These observations will provide high-resolution spectra that
will allow us to deconvolve and constrain the primary continuum, the
multiple absorbers, the narrow and broad iron lines, the local and
distant reflections and the soft excess.
Title : INVESTIGATION ON MRK 335 IN AN INTERMEDIATE STATE
PI: Boissay-Malaquin
Abstract: We propose a DDT observation of the highly variable Narrow-Line
Seyfert 1 Mrk 335 with Chandra/HETG (150 ks DDT + 90 ks GTO). Because
of a pending observation accepted for cycle 5, NuSTAR will join such
Chandra observation on a best effort basis. We also seek to obtain a
contemporaneous NICER DDT observation. We aim to characterize the warm
absorbers previously detected in XMM-Newton/RGS data. We aim to
observe Mrk 335 in the next 10-20 days, while it has an intermediate
flux, ideal state for the detection of the absorbers. Observing now
ensures that we will catch the adequate intermediate state (according
to the Swift monitoring), but also offers a unique view of an AGN when
it is turning on again, after being in a low flux state for the past 2
years. These observations will provide high-resolution spectra that
will allow us to deconvolve and constrain the primary continuum, the
multiple absorbers, the narrow and broad iron lines, the local and
distant reflections and the soft excess.
Title : INVESTIGATION ON MRK 335 IN AN INTERMEDIATE STATE
PI: Boissay-Malaquin
Abstract: We propose a DDT observation of the highly variable Narrow-Line
Seyfert 1 Mrk 335 with Chandra/HETG (150 ks DDT + 90 ks GTO). Because
of a pending observation accepted for cycle 5, NuSTAR will join such
Chandra observation on a best effort basis. We also seek to obtain a
contemporaneous NICER DDT observation. We aim to characterize the warm
absorbers previously detected in XMM-Newton/RGS data. We aim to
observe Mrk 335 in the next 10-20 days, while it has an intermediate
flux, ideal state for the detection of the absorbers. Observing now
ensures that we will catch the adequate intermediate state (according
to the Swift monitoring), but also offers a unique view of an AGN when
it is turning on again, after being in a low flux state for the past 2
years. These observations will provide high-resolution spectra that
will allow us to deconvolve and constrain the primary continuum, the
multiple absorbers, the narrow and broad iron lines, the local and
distant reflections and the soft excess.
Title : INVESTIGATION ON MRK 335 IN AN INTERMEDIATE STATE
PI: Boissay-Malaquin
Abstract: We propose a DDT observation of the highly variable Narrow-Line
Seyfert 1 Mrk 335 with Chandra/HETG (150 ks DDT + 90 ks GTO). Because
of a pending observation accepted for cycle 5, NuSTAR will join such
Chandra observation on a best effort basis. We also seek to obtain a
contemporaneous NICER DDT observation. We aim to characterize the warm
absorbers previously detected in XMM-Newton/RGS data. We aim to
observe Mrk 335 in the next 10-20 days, while it has an intermediate
flux, ideal state for the detection of the absorbers. Observing now
ensures that we will catch the adequate intermediate state (according
to the Swift monitoring), but also offers a unique view of an AGN when
it is turning on again, after being in a low flux state for the past 2
years. These observations will provide high-resolution spectra that
will allow us to deconvolve and constrain the primary continuum, the
multiple absorbers, the narrow and broad iron lines, the local and
distant reflections and the soft excess.
Title : INVESTIGATION ON MRK 335 IN AN INTERMEDIATE STATE
PI: Boissay-Malaquin
Abstract: We propose a DDT observation of the highly variable Narrow-Line
Seyfert 1 Mrk 335 with Chandra/HETG (150 ks DDT + 90 ks GTO). Because
of a pending observation accepted for cycle 5, NuSTAR will join such
Chandra observation on a best effort basis. We also seek to obtain a
contemporaneous NICER DDT observation. We aim to characterize the warm
absorbers previously detected in XMM-Newton/RGS data. We aim to
observe Mrk 335 in the next 10-20 days, while it has an intermediate
flux, ideal state for the detection of the absorbers. Observing now
ensures that we will catch the adequate intermediate state (according
to the Swift monitoring), but also offers a unique view of an AGN when
it is turning on again, after being in a low flux state for the past 2
years. These observations will provide high-resolution spectra that
will allow us to deconvolve and constrain the primary continuum, the
multiple absorbers, the narrow and broad iron lines, the local and
distant reflections and the soft excess.
Title : Detecting the softening of emission in quiescence in a supermassive
black hole
PI: Wevers
Abstract: Tidal disruptions of stars by supermassive black holes (SMBHs) have
long been proposed as probes of accretion state transitions around
SMBHs. However, due to a combination of lack of accurate physical
models and dedicated X-ray (corona) and UV (disk) monitoring programs,
such events have not yet been identified. We have been tracking the
first such case over the last 600+ days using the X-ray and UV data
from Swift, NICER, and XMM-Newton (see Fig. 1 of science
justification). During this time the source underwent two state
transitions, the only known SMBH to undergo such extreme and rapid
accretion regime changes, and now it is approaching a quiescent state.
Here, we propose for a 50 ks Chandra exposure, an estimated factor of
10 deeper than a recent XMM observation, to test various (currently
unconstrained) models of accretion physics.
Title : Unpicking the threads of a rare collapsar explosion
PI: Troja
Abstract: GRB190829A is a rare nearby (z=0.08) gamma-ray burst of long duration,
followed by a bright Type Ic supernova. Recently it was proposed that
events like GRB190829A could produce large amounts of heavy metals,
and be the dominant sources of galactic r-process enrichment . The
characteristic signature would be a long-lived infrared emission,
outshining the supernova light months after the explosion. The main
obstacle in identifying this novel emission component is the bright
GRB afterglow. Continued X-ray monitoring of this GRB would
characterize its non-thermal emission, and allow us to disentangle the
afterglow contribution from any possible red excess. Only Chandra can
resolve the GRB counterpart from nearby contaminating sources.
Title : Get to the Chopper!!! - Testing the Propeller Nature of the Off-States
in the ULX Pulsar NGC7793 P13
PI: Walton
Abstract: NGC7793 P13, one of the few ULXs known to be powered by a neutron
star, has recently entered an 'off-state' (i.e its flux is >10x below
its 'normal' ULX level). These may be related to the propeller effect,
and may offer an opportunity to determine the B-field (still hotly
debated). Based on its previous off-state (0.3-10 keV flux of ~3-6e-14
erg/cm^2/s), simulations suggest that a deep observation with XMM
could still detect pulsations if they are present, allowing us to
probe the nature of these rare and potentially key events. In order to
determine whether this is feasible for the new off-state we need to
confirm the current flux of the source, but this is now below the
detection capabilities of Swift. We are therefore requesting a short
DDT observation with Chandra. In addition, the excellent spatial
resolution will allow us to test whether the emission is point-like or
extended, following the detection of extended emission in an off-state
seen from the ULX pulsar NGC5907 ULX1.
Title : Light echoes from the magnetar, SGR J1935+2154
PI: Gogus
Abstract: SGR 1935+2154 is one of the most burst prolific transient magnetars:
It was discovered in 2014 with Swift-BAT after emitting short duration
magnetar-like bursts, and exhibited three activity episodes in 2016,
2017, 2019 and a fourth one, which started a day ago. More than 35
bursts were recorded from the source in the last 24 hours (ATel 13675:
Palmer et al. 2020, GCN 27657: Barthelmy et al., 2020), MAXI (GCN
27661: Sugawara, Y. et al., 2020) as well as Fermi (GCN 27659:
Fletcher, C. et al., 2020) and Calet GBM (GCN 27663: Ricciarini et al.
2020). Swift XRT has also collected data in PC mode for about 2 ks in
response to the Swift trigger (#968211). We clearly detect an X-ray
ring around the source in this short exposure. The emission around the
source is also quite extended, reaching to about 0.5'. We propose a 10
ks pointing with ACIS-I to explore the ring, search for other rings
and a possible wind nebula powered by the magnetar.
Title : Grating spectroscopy of the unexpectedly bright comet C/2019 Y4 ATLAS
PI: Bodewits
Abstract: Our observations will also allow us to study the temporal development
of the X-ray emission from Comet ATLAS under its rapidly changing
conditions. ATLAS is an Oort cloud comet discovered in December 2019
(MPEC 2020-A112). Based on its current brightness and behavior, it is
expected to become a naked-eye object in May and possibly the
brightest comet seen in the last decade. This provides a unique
opportunity to observe the comet with the Chandra gratings to acquire
a high resolution X-ray spectrum that allows us to resolve the low
energy line emission (< 300eV; Snios et al. 2016), to test new
theories about how solar wind charge exchange emission lines ratios
are affected by the composition of the neutral gas around comets
(Mullen et al. 2017), and to investigate the curious lines in the 1 to
2 keV region (Ewing et al. 2013).
Title : Grating spectroscopy of the unexpectedly bright comet C/2019 Y4 ATLAS
PI: Bodewits
Abstract: Our observations will also allow us to study the temporal development
of the X-ray emission from Comet ATLAS under its rapidly changing
conditions. ATLAS is an Oort cloud comet discovered in December 2019
(MPEC 2020-A112). Based on its current brightness and behavior, it is
expected to become a naked-eye object in May and possibly the
brightest comet seen in the last decade. This provides a unique
opportunity to observe the comet with the Chandra gratings to acquire
a high resolution X-ray spectrum that allows us to resolve the low
energy line emission (< 300eV; Snios et al. 2016), to test new
theories about how solar wind charge exchange emission lines ratios
are affected by the composition of the neutral gas around comets
(Mullen et al. 2017), and to investigate the curious lines in the 1 to
2 keV region (Ewing et al. 2013).
Title : Grating spectroscopy of the unexpectedly bright comet C/2019 Y4 ATLAS
PI: Bodewits
Abstract: Our observations will also allow us to study the temporal development
of the X-ray emission from Comet ATLAS under its rapidly changing
conditions. ATLAS is an Oort cloud comet discovered in December 2019
(MPEC 2020-A112). Based on its current brightness and behavior, it is
expected to become a naked-eye object in May and possibly the
brightest comet seen in the last decade. This provides a unique
opportunity to observe the comet with the Chandra gratings to acquire
a high resolution X-ray spectrum that allows us to resolve the low
energy line emission (< 300eV; Snios et al. 2016), to test new
theories about how solar wind charge exchange emission lines ratios
are affected by the composition of the neutral gas around comets
(Mullen et al. 2017), and to investigate the curious lines in the 1 to
2 keV region (Ewing et al. 2013).
Title : Grating spectroscopy of the unexpectedly bright comet C/2019 Y4 ATLAS
PI: Bodewits
Abstract: Our observations will also allow us to study the temporal development
of the X-ray emission from Comet ATLAS under its rapidly changing
conditions. ATLAS is an Oort cloud comet discovered in December 2019
(MPEC 2020-A112). Based on its current brightness and behavior, it is
expected to become a naked-eye object in May and possibly the
brightest comet seen in the last decade. This provides a unique
opportunity to observe the comet with the Chandra gratings to acquire
a high resolution X-ray spectrum that allows us to resolve the low
energy line emission (< 300eV; Snios et al. 2016), to test new
theories about how solar wind charge exchange emission lines ratios
are affected by the composition of the neutral gas around comets
(Mullen et al. 2017), and to investigate the curious lines in the 1 to
2 keV region (Ewing et al. 2013).
Title : Grating spectroscopy of the unexpectedly bright comet C/2019 Y4 ATLAS
PI: Bodewits
Abstract: Our observations will also allow us to study the temporal development
of the X-ray emission from Comet ATLAS under its rapidly changing
conditions. ATLAS is an Oort cloud comet discovered in December 2019
(MPEC 2020-A112). Based on its current brightness and behavior, it is
expected to become a naked-eye object in May and possibly the
brightest comet seen in the last decade. This provides a unique
opportunity to observe the comet with the Chandra gratings to acquire
a high resolution X-ray spectrum that allows us to resolve the low
energy line emission (< 300eV; Snios et al. 2016), to test new
theories about how solar wind charge exchange emission lines ratios
are affected by the composition of the neutral gas around comets
(Mullen et al. 2017), and to investigate the curious lines in the 1 to
2 keV region (Ewing et al. 2013).
Title : Grating spectroscopy of the unexpectedly bright comet C/2019 Y4 ATLAS
PI: Bodewits
Abstract: Our observations will also allow us to study the temporal development
of the X-ray emission from Comet ATLAS under its rapidly changing
conditions. ATLAS is an Oort cloud comet discovered in December 2019
(MPEC 2020-A112). Based on its current brightness and behavior, it is
expected to become a naked-eye object in May and possibly the
brightest comet seen in the last decade. This provides a unique
opportunity to observe the comet with the Chandra gratings to acquire
a high resolution X-ray spectrum that allows us to resolve the low
energy line emission (< 300eV; Snios et al. 2016), to test new
theories about how solar wind charge exchange emission lines ratios
are affected by the composition of the neutral gas around comets
(Mullen et al. 2017), and to investigate the curious lines in the 1 to
2 keV region (Ewing et al. 2013).
Title : Grating spectroscopy of the unexpectedly bright comet C/2019 Y4 ATLAS
PI: Bodewits
Abstract: Our observations will also allow us to study the temporal development
of the X-ray emission from Comet ATLAS under its rapidly changing
conditions. ATLAS is an Oort cloud comet discovered in December 2019
(MPEC 2020-A112). Based on its current brightness and behavior, it is
expected to become a naked-eye object in May and possibly the
brightest comet seen in the last decade. This provides a unique
opportunity to observe the comet with the Chandra gratings to acquire
a high resolution X-ray spectrum that allows us to resolve the low
energy line emission (< 300eV; Snios et al. 2016), to test new
theories about how solar wind charge exchange emission lines ratios
are affected by the composition of the neutral gas around comets
(Mullen et al. 2017), and to investigate the curious lines in the 1 to
2 keV region (Ewing et al. 2013).
Title : Grating spectroscopy of the unexpectedly bright comet C/2019 Y4 ATLAS
PI: Bodewits
Abstract: Our observations will also allow us to study the temporal development
of the X-ray emission from Comet ATLAS under its rapidly changing
conditions. ATLAS is an Oort cloud comet discovered in December 2019
(MPEC 2020-A112). Based on its current brightness and behavior, it is
expected to become a naked-eye object in May and possibly the
brightest comet seen in the last decade. This provides a unique
opportunity to observe the comet with the Chandra gratings to acquire
a high resolution X-ray spectrum that allows us to resolve the low
energy line emission (< 300eV; Snios et al. 2016), to test new
theories about how solar wind charge exchange emission lines ratios
are affected by the composition of the neutral gas around comets
(Mullen et al. 2017), and to investigate the curious lines in the 1 to
2 keV region (Ewing et al. 2013).
Title : Grating spectroscopy of the unexpectedly bright comet C/2019 Y4 ATLAS
PI: Bodewits
Abstract: Our observations will also allow us to study the temporal development
of the X-ray emission from Comet ATLAS under its rapidly changing
conditions. ATLAS is an Oort cloud comet discovered in December 2019
(MPEC 2020-A112). Based on its current brightness and behavior, it is
expected to become a naked-eye object in May and possibly the
brightest comet seen in the last decade. This provides a unique
opportunity to observe the comet with the Chandra gratings to acquire
a high resolution X-ray spectrum that allows us to resolve the low
energy line emission (< 300eV; Snios et al. 2016), to test new
theories about how solar wind charge exchange emission lines ratios
are affected by the composition of the neutral gas around comets
(Mullen et al. 2017), and to investigate the curious lines in the 1 to
2 keV region (Ewing et al. 2013).
Title : Chandra observations of the newly discovered magnetar Swift
J1818.0-1607
PI: Blumer
Abstract: Magnetars are young neutron stars believed to be powered by their
super-strong magnetic fields and exhibiting a diverse set of
observational properties. They go through long periods of quiescence,
interrupted by bursting activity over the course of days to months
that are followed by spectral and temporal changes. Magnetar activity
has also been recently observed in other pulsar classes. In this
proposal, we request Chandra observations of Swift J1818.0-1607, a
magnetar candidate discovered by Swift on 12 March 2020 and having a
1.36-s periodicity discovered by follow-up NICER observations. The
main scientific goals here are to detect and localize the X-ray
source, constrain its imaging and spectral properties, and confirm the
magnetar nature by studying its spectrum in comparison to other
magnetars. If detected in this DDT, we will separately propose for
follow-up and more detailed X-ray studies of this source.
Title : Proof of concept for the detection of non-burning symbiotic binaries
PI: Lucy
Abstract: Non-burning symbiotic binaries--powered by the accretion of a cool
giant onto a white dwarf (WD), without shell burning on the WD--are
extremely difficult to find, which is why less than 5% of known
symbiotic stars are non-burning. But the true population of
non-burning symbiotics is likely much larger, and may hold the key to
testing how the large disks of symbiotics drive jets and winds. In
this PhD thesis work, we developed a novel strategy for finding
non-burning symbiotics using uvg colors and minutes-timescale
variability in SkyMapper. In 2019 Sep-Oct, we obtained Swift followup
observations of our top two non-burning symbiotic candidates, IRAS
15175-4508 and Haro 1-10, showing a 2sig X-ray detection and 4sig UV
flickering, respectively. We request Chandra observations of IRAS
15175-4508 and Haro 1-10 to confirm the presence of their accretion
disks before their high states end, and to validate our method of
uncovering this hidden population of supernova progenitor candidates.
Title : Proof of concept for the detection of non-burning symbiotic binaries
PI: Lucy
Abstract: Non-burning symbiotic binaries--powered by the accretion of a cool
giant onto a white dwarf (WD), without shell burning on the WD--are
extremely difficult to find, which is why less than 5% of known
symbiotic stars are non-burning. But the true population of
non-burning symbiotics is likely much larger, and may hold the key to
testing how the large disks of symbiotics drive jets and winds. In
this PhD thesis work, we developed a novel strategy for finding
non-burning symbiotics using uvg colors and minutes-timescale
variability in SkyMapper. In 2019 Sep-Oct, we obtained Swift followup
observations of our top two non-burning symbiotic candidates, IRAS
15175-4508 and Haro 1-10, showing a 2sig X-ray detection and 4sig UV
flickering, respectively. We request Chandra observations of IRAS
15175-4508 and Haro 1-10 to confirm the presence of their accretion
disks before their high states end, and to validate our method of
uncovering this hidden population of supernova progenitor candidates.
Title : A Candidate Low-luminosity Gamma-ray Burst Identified by an Early
Optical Flash
PI: Ho
Abstract: Low-luminosity gamma-ray bursts (LLGRBs) are a rare class of
explosions with a relativistic energy release 2-3 orders of magnitude
smaller than that from classical GRBs. Due to their lower luminosities
they are only discovered nearby (z<0.1), so despite being 100x more
common than classical GRBs only seven have ever been discovered and
their origins remain unknown.
All LLGRBs are accompanied by a Type Ic-BL supernova (SN). Two events
(GRB060218/SN2006aj, GRB100316D/SN2010bh) have Chandra observations
from 10 to 40 days post-explosion that reveal an excess of soft X-ray
emission that may arise from a long-lived central engine such as an
accreting black hole or a magnetar. Early optical observations of
SN2006aj revealed a fast (<2d) blue flash prior to the onset of the
SN.
SN2020bvc (z=0.025) is a Ic-BL with an early blue flash similar to
SN2006aj (Astronote #2020-37). We propose Chandra observations to test
whether there is relativistic ejecta and compare this event to other
LLGRBs.
Title : A Candidate Low-luminosity Gamma-ray Burst Identified by an Early
Optical Flash
PI: Ho
Abstract: Low-luminosity gamma-ray bursts (LLGRBs) are a rare class of
explosions with a relativistic energy release 2-3 orders of magnitude
smaller than that from classical GRBs. Due to their lower luminosities
they are only discovered nearby (z<0.1), so despite being 100x more
common than classical GRBs only seven have ever been discovered and
their origins remain unknown.
All LLGRBs are accompanied by a Type Ic-BL supernova (SN). Two events
(GRB060218/SN2006aj, GRB100316D/SN2010bh) have Chandra observations
from 10 to 40 days post-explosion that reveal an excess of soft X-ray
emission that may arise from a long-lived central engine such as an
accreting black hole or a magnetar. Early optical observations of
SN2006aj revealed a fast (<2d) blue flash prior to the onset of the
SN.
SN2020bvc (z=0.025) is a Ic-BL with an early blue flash similar to
SN2006aj (Astronote #2020-37). We propose Chandra observations to test
whether there is relativistic ejecta and compare this event to other
LLGRBs.
Title : The Dimming of Betelgeuse
PI: Kashyap
Abstract: Betelgeuse (M2Iab) is a prime candidate for an impending supernova. It
has been exhibiting an unprecedented dimming (Guinan & Wasatonic, ATEL
13410), dropping in luminosity by ~25% since Sep 2019. Prima facie
this cannot be attributed to adiabatic upwelling of higher temperature
material which explains its usual variability (see Dolan et al. 2016,
ApJ 819, 7). The stellar radius has decreased by 9% in 5 months (cf.
free-fall timescale t_ff~0.6 yr), suggesting that it is undergoing
significant structural changes due to a switchover from He- to
C-burning. This presents an unprecedented opportunity to observe the
process and detect the presence of high-energy processes should they
exist. Any detection of X-rays will be of fundamental importance to
understand the phenomenon being exhibited by Betelgeuse. If
undetected, we will set stringent upper limits to the X-ray flux by
combining these data with prior Chandra Cal observations.
Title : The Dimming of Betelgeuse
PI: Kashyap
Abstract: Betelgeuse (M2Iab) is a prime candidate for an impending supernova. It
has been exhibiting an unprecedented dimming (Guinan & Wasatonic, ATEL
13410), dropping in luminosity by ~25% since Sep 2019. Prima facie
this cannot be attributed to adiabatic upwelling of higher temperature
material which explains its usual variability (see Dolan et al. 2016,
ApJ 819, 7). The stellar radius has decreased by 9% in 5 months (cf.
free-fall timescale t_ff~0.6 yr), suggesting that it is undergoing
significant structural changes due to a switchover from He- to
C-burning. This presents an unprecedented opportunity to observe the
process and detect the presence of high-energy processes should they
exist. Any detection of X-rays will be of fundamental importance to
understand the phenomenon being exhibited by Betelgeuse. If
undetected, we will set stringent upper limits to the X-ray flux by
combining these data with prior Chandra Cal observations.
Title : The nearby TypeIc/Ic-BL SN2020oi in M100 (d~16 Mpc)
PI: Stroh
Abstract: SN2020oi is a young type Ic/Ic-BL SN in the very nearby galaxy M100
(16 Mpc). We request X-ray follow-up in coordination with follow-up
across the spectrum with the primary objective to constrain the shock
velocity and the density in the nearby environment of the explosion.
Title : The nearby TypeIc/Ic-BL SN2020oi in M100 (d~16 Mpc)
PI: Stroh
Abstract: SN2020oi is a young type Ic/Ic-BL SN in the very nearby galaxy M100
(16 Mpc). We request X-ray follow-up in coordination with follow-up
across the spectrum with the primary objective to constrain the shock
velocity and the density in the nearby environment of the explosion.
Title : Chandra Observation of SN 2019yvq
PI: Pooley
Abstract: In 15 ksec of merged Swift/XRT observations since Dec 29, there are
26.1 +/- 6.0 net counts (0.2-10 keV) in a 45" aperture centered on the
Type Ia SN 2019yvq in NGC 4441 (19 Mpc). In a previous Swift
observation of the field from 2012, using the same source and
background regions, 7.1 +/- 3.5 net counts are detected. The clear
detection of an X-ray source in the new data may be from the SN or
possibly from an unrelated source. Chandra's sensitivity and spatial
resolution are necessary to determine the origin of the X-rays.
Title : Follow-up of a Weak-Line Quasar with Extreme X-ray Variability
PI: Ni
Abstract: We request an observation of SDSS J1539+3954, a weak-line quasar (WLQ)
that exhibited extreme X-ray variability, to monitor its potential
change in X-ray flux. In Sept 2019, we unexpectedly discovered that
the X-ray flux of SDSS J1539+3954 had increased by a factor of > 20.
Before this rise, it appeared X-ray weak compared with the expectation
from its UV flux; after the rise, the ratio of its X-ray flux and UV
flux is consistent with the majority of the AGN population. In the
context of the thick inner accretion-disk model we proposed for WLQs,
the extreme X-ray variability could arise due to a slight change in
the thickness of the disk that moved across our line of sight. When
our line of sight intercepts the disk, we observe an X-ray weak state;
when it misses the disk, we observe an X-ray normal state. Monitoring
the potential X-ray state transition before the next Chandra CfP will
greatly help to constrain the timescale of such transitions, thus
probing the accretion-disk physics.
Title : Intrabinary shock emission of the black widow candidate 4FGL
J0336.0+7502
PI: Li
Abstract: Many millisecond pulsars are in binary and some special ones are in
compact orbits, whose the periods are less than 1d. Depending on the
companion type, these MSPs are named black widow or redback. The
binary members in a black widow/redback are just separated by a few
solar radii. Under this extreme condition, pulsar intrabinary shock
(IBS), where the stellar/pulsar winds severely collides, is formed.
One side of the tidally-locked companion is heated by IBS that results
in orbital modulation in optical. The X-ray emission will also be
modulated by Doppler boosting. 4FGL J0336.0+7502 is a strong black
widow candidate, which was recently identified by our MSP hunting
campaign. Not only showing gamma-ray properties comparable to other
black widows, an optical counterpart that exhibits 3.72-h modulation
was also found. An X-ray counterpart is detected by Swift/XRT in 2012,
but just marginally. We propose a 15ks (~1 orbit) Chandra observation
to confirm the detection and study the IBS.
Title : UNEXPECTED EARLY PERIASTRON PASSAGE AND ECLIPSE IN THE SYMBIOTIC
SYSTEM R AQR
PI: Karovska
Abstract: We propose a 50ks ACIS-S DDT observation of the interacting symbiotic
binary (where a WD accretes from the powerful wind of an evolved
giant), RAqr. The white dwarf accretor is making an unexpected early
approach to the mass donor Mira star. The enhanced activity in the
system has resulted in a powerful outburst and mass ejection, leading
to dust formation eclipsing the donor star, as evidenced by the recent
dramatic dimming of the optical light of RAqr. Symbiotic systems are
of great importance because they are likely progenitors of a fraction
of asymmetric Planetary Nebulae (PN), and of cosmological distance
indicator SN Ia. Understanding the characteristics of the accretion
onto the WD, and of the surrounding environment, especially during
powerful mass-loss events and outbursts around periastron, are crucial
steps to determine the precursor conditions for formation of PN and SN
Ia. ToO observing time has been granted recently on JVLA , HST, and
Swift to study this rare event.
Title : X-ray jet at very high redshift
PI: moretti
Abstract: Powerful radio-loud QSOs emit relativistic jets of plasma. At high
redshift, their X-ray emission is thought to be partially due to the
interaction of the plasma with the CMB photons. Since CMB photon
density strongly evolves with redshift, radio-loud QSO X-ray
luminosity is expected to quickly increase in the early Universe. We
propose to observe PSO0309+47, the most luminous X-ray and radio QSO
recently discovered at z>6.0. Its redshift (z=6.1) and the QSO nature
has been confirmed by optical LBT spectrum in October 2019. A short
Swift-XRT observation, in November 2019, allowed us to roughly
estimate its X-ray spectral properties. Interestingly, the position of
the X-ray counterpart is (marginally) inconsistent with the optical
one. This could be interpreted as the signature of a jet interacting
with the CMB photons. A Chandra 25Ks observation, with 50 source
photons expected, would be able to confirm the positional offset and
to assess the extension of the source.
Title : An accurate position of a new ULX in NGC 4045
PI: Brightman
Abstract: We recently detected a new X-ray source with Swift/XRT that appears to
be associated with the galaxy NGC 4045 (D=32 Mpc). The source was
first detected by Swift on 2019-12-04 and the latest detection was on
2019-12-06 with a count rate of 1.4E-02+/-3.3E-03 ct/s. The spectrum
can be described by a powerlaw with Gamma=1.1+/-0.7. The 0.3--10 keV
flux is 6.8E-13 ergs/cm2/s, which at a distance of 32 Mpc corresponds
to a luminosity of 6.3E+40 erg/s. The source is likely a new ULX. No
previous X-ray source has been catalogued within several armin of this
source. Observations with Swift several months prior yielded only
upper limits below the current count rate. We request a 10-ks Chandra
observation in order to obtain an accurate position that will
potentially enable the identification of an optical/NIR counterpart.
An OIR counterpart could yield information about the donor star of the
ULX. The 90% positional uncertainty from Swift is only 5.1" and would
yield several counterpart candidates.
Title : Chandra Observations of the Interstellar Comet C/2019 Q4 Borisov
PI: Snios
Abstract: Comet 2019/Q4 Borisov is only the second-known interstellar object
detected within the Solar System, and the first to be discovered prior
to reaching its perihelion. This presents a unique opportunity to
extensively observe this exotic comet during its closest approach to
Earth prior to its exit from the Solar System. X-ray observations of
C/2019 Q4 may be used to measure dust and gas outflow rates from the
source, neutral particle interactions with Solar Wind, and variations
in outflow rates and morphology. These properties may also be compared
against Solar System comets/asteroids to probe for differences, if
any, with the exosolar object. We therefore propose to observe C/2019
Q4 with Chandra HRC during its perihelion on 27-Dec-2019 to quantify
the afore-mentioned physical properties of this interstellar comet.
Title : Chandra Observations of the Interstellar Comet C/2019 Q4 Borisov
PI: Snios
Abstract: Comet 2019/Q4 Borisov is only the second-known interstellar object
detected within the Solar System, and the first to be discovered prior
to reaching its perihelion. This presents a unique opportunity to
extensively observe this exotic comet during its closest approach to
Earth prior to its exit from the Solar System. X-ray observations of
C/2019 Q4 may be used to measure dust and gas outflow rates from the
source, neutral particle interactions with Solar Wind, and variations
in outflow rates and morphology. These properties may also be compared
against Solar System comets/asteroids to probe for differences, if
any, with the exosolar object. We therefore propose to observe C/2019
Q4 with Chandra HRC during its perihelion on 27-Dec-2019 to quantify
the afore-mentioned physical properties of this interstellar comet.
Title : Chandra Observations of the Interstellar Comet C/2019 Q4 Borisov
PI: Snios
Abstract: Comet 2019/Q4 Borisov is only the second-known interstellar object
detected within the Solar System, and the first to be discovered prior
to reaching its perihelion. This presents a unique opportunity to
extensively observe this exotic comet during its closest approach to
Earth prior to its exit from the Solar System. X-ray observations of
C/2019 Q4 may be used to measure dust and gas outflow rates from the
source, neutral particle interactions with Solar Wind, and variations
in outflow rates and morphology. These properties may also be compared
against Solar System comets/asteroids to probe for differences, if
any, with the exosolar object. We therefore propose to observe C/2019
Q4 with Chandra HRC during its perihelion on 27-Dec-2019 to quantify
the afore-mentioned physical properties of this interstellar comet.
Title : Chandra Observations of the Interstellar Comet C/2019 Q4 Borisov
PI: Snios
Abstract: Comet 2019/Q4 Borisov is only the second-known interstellar object
detected within the Solar System, and the first to be discovered prior
to reaching its perihelion. This presents a unique opportunity to
extensively observe this exotic comet during its closest approach to
Earth prior to its exit from the Solar System. X-ray observations of
C/2019 Q4 may be used to measure dust and gas outflow rates from the
source, neutral particle interactions with Solar Wind, and variations
in outflow rates and morphology. These properties may also be compared
against Solar System comets/asteroids to probe for differences, if
any, with the exosolar object. We therefore propose to observe C/2019
Q4 with Chandra HRC during its perihelion on 27-Dec-2019 to quantify
the afore-mentioned physical properties of this interstellar comet.
Title : Chandra Observations of the Interstellar Comet C/2019 Q4 Borisov
PI: Snios
Abstract: Comet 2019/Q4 Borisov is only the second-known interstellar object
detected within the Solar System, and the first to be discovered prior
to reaching its perihelion. This presents a unique opportunity to
extensively observe this exotic comet during its closest approach to
Earth prior to its exit from the Solar System. X-ray observations of
C/2019 Q4 may be used to measure dust and gas outflow rates from the
source, neutral particle interactions with Solar Wind, and variations
in outflow rates and morphology. These properties may also be compared
against Solar System comets/asteroids to probe for differences, if
any, with the exosolar object. We therefore propose to observe C/2019
Q4 with Chandra HRC during its perihelion on 27-Dec-2019 to quantify
the afore-mentioned physical properties of this interstellar comet.
Title : Simultaneous X-ray and Radio Observations of the Second Localized
Repeating Fast Radio Burst
PI: Scholz
Abstract: We have localized the CHIME/FRB-discovered repeating FRB
180916.J0158+65 to milliarcsecond precision using the European VLBI
Network and identified its host and redshift using Gemini North
observations. This is the second sub-arcsecond localization of a
repeating FRB. The redshift of the host galaxy implies a luminosity
distance at least six times closer than the only other localized
repeater, FRB 121102. Therefore, FRB 180916 can be used to probe much
deeper for X-ray emission from repeating FRBs. We propose to perform
simultaneous observations using Chandra and the 100-m Effelsberg radio
telescope to probe for X-ray emission at the times of radio bursts
from FRB 180916. See attached 1 page science justification for more
information.
Title : Simultaneous X-ray and Radio Observations of the Second Localized
Repeating Fast Radio Burst
PI: Scholz
Abstract: We have localized the CHIME/FRB-discovered repeating FRB
180916.J0158+65 to milliarcsecond precision using the European VLBI
Network and identified its host and redshift using Gemini North
observations. This is the second sub-arcsecond localization of a
repeating FRB. The redshift of the host galaxy implies a luminosity
distance at least six times closer than the only other localized
repeater, FRB 121102. Therefore, FRB 180916 can be used to probe much
deeper for X-ray emission from repeating FRBs. We propose to perform
simultaneous observations using Chandra and the 100-m Effelsberg radio
telescope to probe for X-ray emission at the times of radio bursts
from FRB 180916. See attached 1 page science justification for more
information.
Title : Chandra Observations of the Interstellar Comet C/2019 Q4 Borisov
PI: Snios
Abstract: Comet 2019/Q4 Borisov is only the second-known interstellar object
detected within the Solar System, and the first to be discovered prior
to reaching its perihelion. This presents a unique opportunity to
extensively observe this exotic comet during its closest approach to
Earth prior to its exit from the Solar System. X-ray observations of
C/2019 Q4 may be used to measure dust and gas outflow rates from the
source, neutral particle interactions with Solar Wind, and variations
in outflow rates and morphology. These properties may also be compared
against Solar System comets/asteroids to probe for differences, if
any, with the exosolar object. We therefore propose to observe C/2019
Q4 with Chandra HRC during its perihelion on 27-Dec-2019 to quantify
the afore-mentioned physical properties of this interstellar comet.
Title : Gravitational millilensing as a tool for studying the
microarcsec-scale structure in PKS1413+135
PI: Liodakis
Abstract: We have recently identified a new type of symmetric achromatic
variability (SAV) in light curves of AGN, which we suggest is due to
gravitational lensing. This allows us to probe lenses in the mass
range of 1e3-1e6 solar masses, which have been challenging to detect.
We propose observations of PKS1413+135, which has previously shown 5
SAVs in its radio light curve over the past 27 yrs and now shows
indications that a new event has recently started. Based on previous
events we expect it to continue until 07/2020. This is the first event
ever to be identified while in progress. We expect the X-rays to
follow the same achromatic trend seen in radio, observations of which
are underway. We request 17-4ks-pointings separated by 2 weeks that
will allow us to monitor the X-ray flux evolution during the event and
confirm its achromatic nature. Depending on the outcome, we will have
the unique opportunity to study grav. millilensing, plasma lensing or
intrinsic variability in relativistic jets.
Title : Gravitational millilensing as a tool for studying the
microarcsec-scale structure in PKS1413+135
PI: Liodakis
Abstract: We have recently identified a new type of symmetric achromatic
variability (SAV) in light curves of AGN, which we suggest is due to
gravitational lensing. This allows us to probe lenses in the mass
range of 1e3-1e6 solar masses, which have been challenging to detect.
We propose observations of PKS1413+135, which has previously shown 5
SAVs in its radio light curve over the past 27 yrs and now shows
indications that a new event has recently started. Based on previous
events we expect it to continue until 07/2020. This is the first event
ever to be identified while in progress. We expect the X-rays to
follow the same achromatic trend seen in radio, observations of which
are underway. We request 17-4ks-pointings separated by 2 weeks that
will allow us to monitor the X-ray flux evolution during the event and
confirm its achromatic nature. Depending on the outcome, we will have
the unique opportunity to study grav. millilensing, plasma lensing or
intrinsic variability in relativistic jets.
Title : Gravitational millilensing as a tool for studying the
microarcsec-scale structure in PKS1413+135
PI: Liodakis
Abstract: We have recently identified a new type of symmetric achromatic
variability (SAV) in light curves of AGN, which we suggest is due to
gravitational lensing. This allows us to probe lenses in the mass
range of 1e3-1e6 solar masses, which have been challenging to detect.
We propose observations of PKS1413+135, which has previously shown 5
SAVs in its radio light curve over the past 27 yrs and now shows
indications that a new event has recently started. Based on previous
events we expect it to continue until 07/2020. This is the first event
ever to be identified while in progress. We expect the X-rays to
follow the same achromatic trend seen in radio, observations of which
are underway. We request 17-4ks-pointings separated by 2 weeks that
will allow us to monitor the X-ray flux evolution during the event and
confirm its achromatic nature. Depending on the outcome, we will have
the unique opportunity to study grav. millilensing, plasma lensing or
intrinsic variability in relativistic jets.
Title : Gravitational millilensing as a tool for studying the
microarcsec-scale structure in PKS1413+135
PI: Liodakis
Abstract: We have recently identified a new type of symmetric achromatic
variability (SAV) in light curves of AGN, which we suggest is due to
gravitational lensing. This allows us to probe lenses in the mass
range of 1e3-1e6 solar masses, which have been challenging to detect.
We propose observations of PKS1413+135, which has previously shown 5
SAVs in its radio light curve over the past 27 yrs and now shows
indications that a new event has recently started. Based on previous
events we expect it to continue until 07/2020. This is the first event
ever to be identified while in progress. We expect the X-rays to
follow the same achromatic trend seen in radio, observations of which
are underway. We request 17-4ks-pointings separated by 2 weeks that
will allow us to monitor the X-ray flux evolution during the event and
confirm its achromatic nature. Depending on the outcome, we will have
the unique opportunity to study grav. millilensing, plasma lensing or
intrinsic variability in relativistic jets.
Title : Gravitational millilensing as a tool for studying the
microarcsec-scale structure in PKS1413+135
PI: Liodakis
Abstract: We have recently identified a new type of symmetric achromatic
variability (SAV) in light curves of AGN, which we suggest is due to
gravitational lensing. This allows us to probe lenses in the mass
range of 1e3-1e6 solar masses, which have been challenging to detect.
We propose observations of PKS1413+135, which has previously shown 5
SAVs in its radio light curve over the past 27 yrs and now shows
indications that a new event has recently started. Based on previous
events we expect it to continue until 07/2020. This is the first event
ever to be identified while in progress. We expect the X-rays to
follow the same achromatic trend seen in radio, observations of which
are underway. We request 17-4ks-pointings separated by 2 weeks that
will allow us to monitor the X-ray flux evolution during the event and
confirm its achromatic nature. Depending on the outcome, we will have
the unique opportunity to study grav. millilensing, plasma lensing or
intrinsic variability in relativistic jets.
Title : Exoplanet evaporation in the only known young 4-planet system
PI: Poppenhaeger
Abstract: Exoplanets lose their atmospheres through evaporation driven by
stellar X-ray emission. This leads to a gap observed in exoplanetary
radii; but the physics of evaporation is not well understood. A few
days ago, a new exoplanet system was discovered with 4 low-density and
hence easily evaporable exoplanets and a very young (25 Myr) host star
called V1298 Tau. This is the age at which the bulk of evaporation
should happen, and we can extract key insights on the evaporation
strength from this system if the X-ray luminosity of the host star is
known. ROSAT shows there is a source with a count rate of 0.15 cps
near the position of the star (Lx=2e30 erg/s). But there are 2 other
young stars in the ROSAT PSF (the smallest separation being 25
arcsec), so it is unclear if or how much of the flux stems from the
exoplanet host star. We ask for 1 ks of Chandra time with ACIS-S. This
will yield 70 counts in total, and we will easily determine how much
flux stems from the exoplanet host star.
Title : GRS 1915+105 as a Changing-Look Microquasar
PI: Miller
Abstract: GRS 1915+105 is currently in a low flux state, with a flux of about 1
E-10 erg/cm^2/s. This is two orders of magnitude lower than the flux
for which it is famous. Via Swift monitoring, we know that the flux is
diminished partly through internal obscuration. At times, the source
now appears to be Compton-thick. GRS 1915+105 has always been a
Rosetta Stone source that has helped us to better understand quasars.
Now, it appears to be a highly obscured Seyfert-2 or Compton-thick
AGN. Swift spectra give us broad ideas about what might be happening,
but our simulations suggest that 30 ks Chandra/HETGS spectra can
reveal far more, including Doppler broadening of the flux that is
reflected by the obscuring material, and highly ionized outflows. It
may be the case that the obscuring material is actually an extreme
outflow, and that the source is losing more mass than it accretes. An
email has been sent to the director with a plot from one simulation.
Title : GRS 1915+105 as a Changing-Look Microquasar
PI: Miller
Abstract: GRS 1915+105 is currently in a low flux state, with a flux of about 1
E-10 erg/cm^2/s. This is two orders of magnitude lower than the flux
for which it is famous. Via Swift monitoring, we know that the flux is
diminished partly through internal obscuration. At times, the source
now appears to be Compton-thick. GRS 1915+105 has always been a
Rosetta Stone source that has helped us to better understand quasars.
Now, it appears to be a highly obscured Seyfert-2 or Compton-thick
AGN. Swift spectra give us broad ideas about what might be happening,
but our simulations suggest that 30 ks Chandra/HETGS spectra can
reveal far more, including Doppler broadening of the flux that is
reflected by the obscuring material, and highly ionized outflows. It
may be the case that the obscuring material is actually an extreme
outflow, and that the source is losing more mass than it accretes. An
email has been sent to the director with a plot from one simulation.
Title : Chasing high energy emission from neutron star black holes merger
PI: Jaodand
Abstract: GW170817 opened up a new, interesting question in astronomy- what
would a neutron star black hole (NSBH) merger look like. In case of
such merger below a certain mass threshold where the NS is tidally
disrupted beyond an innermost stable circular orbit we expect to see a
bright red kilonova accompanied by a high mass tidal ejecta up to 0.1
M_Sun. Very recently, on August 14, LIGO/Virgo observatories jointly
detected a very promising NS-BH event (LIGO/Virgo S190814bv).
Detection of rising radio counterpart with ASKAP makes it first NS-BH
merger with a multi-wavelength counterpart, suggesting polar ejecta
launch from the system. Understanding the event with complimentary
high energy observations would shed critical light on neutron star
disruption process by a BH and ultimately allow us to understand the
state of matter and NS composition. Swift initially carried out 451
triggered observations of the LVC region with no counterpart. We dont
see a Swift counterpart in todays observation.
Title : The recurrent nova outburst of V3890 Sgr
PI: Orio
Abstract: The symbiotic recurrent nova (RN) V3890 Sgr is having its third known
outburst. Symbiotic RN are strong X-ray sources since the first days.
The Chandra HETG spectrum of RS Oph on day 13 showed strong emission
lines of a multi-temperature plasma, due to the red giant wind
shock-heated by the new, "violent" outflow (Nelson et al. 2008, ApJ
637, 1067; Ness et al. 2009, ApJ 137, 3414). The derived plasma
temperature and the emission line profile are used to constrain the
mass of the ejecta and the outflow geometry, as done by Drake et al.
(2015, ApJ 825, 95) and Orlando et al. (2017, MNRAS 464, 5003) for the
outburst of V745 Sco. In RS Oph and V745 Sco, both hosting massive
white dwarfs, the ejected mass was lower than the accreted envelope,
yielding credibility to symbiotic recurrent novae as a channel to
supernovae Ia explosions. The present outburst of V3890 Sgr will give
important terms of comparison for the outflow models and the possible
path to SN Ia.
Title : Catching the return to quiescence of a classical nova post-explosion
system: the unique opportunity for V1369 Cen
PI: Drake
Abstract: The central role of a thermonuclear runaway and explosive envelope
ejection in classical novae (CN) is well established but how, and if,
the system relaxes back to its pre-CN state is unknown. The immediate
aftermath, when accretion restarts and a disk reappears, is crucial
for the initial conditions for any subsequent explosion and the
presumed path toward the cataclysmic variable stage. Understanding
this vital phase requires observing fresh post-CN systems, where
X-rays are essential for diagnosing renewed accretion. This is
extremely difficult because CN are usually distant, obscured and very
faint. CN V1369 Cen 2013 is the best chance to make these
observations. Recent optical-NIR VLT spectra indicate a disk-like
structure is reforming, while Swift data show possible evidence of
renewed accretion. However, Swift could be seeing CN ejecta and
spectral quality is too poor to diagnose the source nature. Chandra
can make the crucial observations to understand the state of the
source.
Title : Imaging of Swift J1728.9-3613
PI: Miller
Abstract: The SJ has been sent in an email to the Director.
Title : Propeller effect in 4U1901+03 - measuring the spectrum after the
transition
PI: Lutovinov
Abstract: We are asking to observe the transient HMXB 4U1901+03, that recently
went into an outburst. XRT observations showed a dramatic decrease in
the source flux - 30 times in 3 days. This sudden dimming is
reminiscent of an onset of the propeller effect similar to other
well-known HMXBs. The source is currently in a low-luminosity state
with the flux of 5e-13 erg/cm2/s (0.5-10 keV). Because of this low
flux we are asking Chandra observations in order to measure the
spectrum of 4U1901+03, a few days after the transition to the
propeller regime to finally confirm it and to determine the spectral
parameters. It also should be noted that there are no a visibility of
this source with XMM-Newton, so only Chandra can help in the solving
the problem. We are asking for the 10 ks observation. Using PIMMS we
estimated that it will be enough to measure accurately the spectral
shape and to understand is it blackbody-like or are there any
deviations from it.
Title : HETG Study of Emission & Absorption Lines in X-ray Bursts from 4U
1820-30
PI: Heinke
Abstract: Strohmayer+2019 saw an emission line (1.04 keV) and two absorption
lines (1.7, 3.0 keV) during the peak of NICER PRE bursts from 4U
1820-30. The lines occur reproducibly in multiple bursts, and are
clearly present in each of the 4 brightest bursts. The energies are
4.6% bluer in brighter than fainter bursts; gravitational or
wind-induced shift? NICER cannot resolve the lines (<70 eV). 4U
1820-30 often (but not always) undergoes low/hard states at six-month
intervals, and strong PRE bursts. NICER has seen bursts every 7 ks in
the last 10 days. The burst lines appear in the PRE phase, ~0.7
seconds each. Simulating these lines (HETG MEG), a single burst is
insufficient; we estimate five PRE bursts will give a >3 sigma
measurement of the 1.7 keV absorption line and 1.04 keV emission line
(the 3 keV absorption feature would likely be only marginally
detected). For a burst every 10 ks, 50 ks should give 5 bursts,
allowing clear HETG detections and measurements.
Title : HETG Study of Emission & Absorption Lines in X-ray Bursts from 4U
1820-30
PI: Heinke
Abstract: Strohmayer+2019 saw an emission line (1.04 keV) and two absorption
lines (1.7, 3.0 keV) during the peak of NICER PRE bursts from 4U
1820-30. The lines occur reproducibly in multiple bursts, and are
clearly present in each of the 4 brightest bursts. The energies are
4.6% bluer in brighter than fainter bursts; gravitational or
wind-induced shift? NICER cannot resolve the lines (<70 eV). 4U
1820-30 often (but not always) undergoes low/hard states at six-month
intervals, and strong PRE bursts. NICER has seen bursts every 7 ks in
the last 10 days. The burst lines appear in the PRE phase, ~0.7
seconds each. Simulating these lines (HETG MEG), a single burst is
insufficient; we estimate five PRE bursts will give a >3 sigma
measurement of the 1.7 keV absorption line and 1.04 keV emission line
(the 3 keV absorption feature would likely be only marginally
detected). For a burst every 10 ks, 50 ks should give 5 bursts,
allowing clear HETG detections and measurements.
Title : The Extended Circumstellar Environment of SN 2003gk
PI: Patnaude
Abstract: The mass loss history of massive stars is one of the least understood
yet fundamental aspects of massive stars. Supernovae shocks, evolving
on timescales of years, allow us to probe 100s to 1000s of years of
stellar evolution, including the crucial time leading up to core
collapse. The X-ray emission from this interaction informs us on the
density and extent of the circumstellar environment, and can provide
clues as to how and when massive stars lose their envelopes, and if
the timing is related to the subsequent core collapse. Observations of
some stripped envelope SNe indicate that the CSM interaction is
delayed, suggesting that the mass loss event occurs on timescales <
10,000 yrs before core collapse. This is in contrast to other Type II
SNe, which can show immediate, strong interaction (IIn) or weak,
extended CSM interaction (IIP/L), suggesting that they type of CSM
interaction is related to the SNe subtype, and may point to a
relationship between progenitor and SN type.
Title : Chandra observation of the gravitationally lensed balzar PKS 1830-211
during its brightest outburst
PI: Buson
Abstract: PKS 1830-211 is a gravitationally lensed blazar at z~2.5 with two
images at ~1" separation which are well resolved in the two earlier
Chandra HETGS images. The blazar is currently undergoing strong
flaring activity at gamma rays. Chandra has carried out observations
during this enhanced state, and demonstrated the effectiveness of
resolving the emission from two images and providing crucial insights.
We propose an additional timely observation, taking advantage of the
newly acquired dataset and upcoming visit.
Title : Chandra observation of the gravitationally lensed balzar PKS 1830-211
during its brightest outburst
PI: Buson
Abstract: PKS 1830-211 is a gravitationally lensed blazar at z~2.5 with two
images at ~1" separation which are well resolved in the two earlier
Chandra HETGS images. The blazar is currently undergoing strong
flaring activity at gamma rays. Chandra has carried out observations
during this enhanced state, and demonstrated the effectiveness of
resolving the emission from two images and providing crucial insights.
We propose an additional timely observation, taking advantage of the
newly acquired dataset and upcoming visit.
Title : The Microquasar GRS 1915+105 in an Unprecedented Quiet State
PI: Miller
Abstract: Right now, GRS 1915+105 is in an unprecedented state: it is 20-50
times fainter in X-rays than typically measured. The source has never
been this faint, and nor for such a long period, in the entire history
of RXTE, Swift, and MAXI monitoring. This state has persisted for
several weeks, but there is no indication for how long it may last. A
Swift XRT snapshot on 4/23 confirms that the source now has a flux of
just 50 mCrab, or about 1 E-9 erg/cm2/s, in the 1-10 keV band. In a
normal state, GRS 1915+105 is observed at 500-2000 mCrab. This
spectrum is itself quite odd, consistent with a very hot blackbody (kT
= 2.4 keV). The most recent MAXI data suggest the flux is a factor of
~2 lower on 4/24. GRS 1915+105 can be observed with the HETGS without
CC mode, and without blocking the zeroth order. This will permit a
spectrum of an unprecedented state in a critical source, and an
examination of the local jet-impacted environment through imaging.
Title : The X-ray obscured quasar J085051: Dust free gas or an eclipse?
PI: Civano
Abstract: Typically, luminous broad line quasar show no or minimal obscuration
in the X-ray band. A small percentage (3%) of X-ray survey selected
sources present broad optical emission lines and mild X-ray
obscuration, supposedly due to dust-free gas not obscuring the broad
line regions. However, given the non simultaneity of the data, a
simple explanation could be that these sources are transitioning from
obscured to unobscured due to e.g. transiting obscuring clouds. The
SDSS broad line quasar J085051 (z=0.66) was recently selected as CCT.
While a bright unobscured spectrum was expected, we observed 60 counts
(0.5-8 keV) and high obscuration (NH=7x10^22pm2.5). We obtained 2 new
optical spectra with the FAST and MDM spectrographs (within 15 and 30
days respectively from the X-ray obsid). Very interestingly we measure
a change in the spectral slope, with the source getting bluer
(difference between the new FAST/MDM spectra and SDSS is m~0.75 at
4300A), confirmed also by new g and r photometry.
Title : Chandra observation of the gravitationally lensed balzar PKS 1830-211
during its brightest outburst
PI: Buson
Abstract: PKS 1830-211 is a gravitationally lensed blazar at z~2.5 with two
images at ~1" separation which are well resolved in the two earlier
Chandra HETGS images. Previous observations show strong NH variations
due to variable obscuration in the source. PKS1830 is currently
undergoing its brightest and longest outburst at gamma-rays and
X-rays. INTEGRAL-IBIS gives a 20-50 keV flux of around 6e-11cgs, ~10x
brighter than during the archival Chandra observations. There is short
term variability. We are monitoring the flare with XRT and Fermi, but
these do not resolve the lensed source images. Macro-lensing and
micro-lensing has been detected in this system. The measurement of the
magnification ratio is of special interest given the contradictory
values found with radio and gamma observations. The 3 Chandra
observations of ~20ks each, which should provide spectra that are much
higher SNR than the archival observation, will allow us to determine
NH and the spectral index for both images.
Title : Chandra observation of the gravitationally lensed balzar PKS 1830-211
during its brightest outburst
PI: Buson
Abstract: PKS 1830-211 is a gravitationally lensed blazar at z~2.5 with two
images at ~1" separation which are well resolved in the two earlier
Chandra HETGS images. Previous observations show strong NH variations
due to variable obscuration in the source. PKS1830 is currently
undergoing its brightest and longest outburst at gamma-rays and
X-rays. INTEGRAL-IBIS gives a 20-50 keV flux of around 6e-11cgs, ~10x
brighter than during the archival Chandra observations. There is short
term variability. We are monitoring the flare with XRT and Fermi, but
these do not resolve the lensed source images. Macro-lensing and
micro-lensing has been detected in this system. The measurement of the
magnification ratio is of special interest given the contradictory
values found with radio and gamma observations. The 3 Chandra
observations of ~20ks each, which should provide spectra that are much
higher SNR than the archival observation, will allow us to determine
NH and the spectral index for both images.
Title : Chandra observation of the gravitationally lensed balzar PKS 1830-211
during its brightest outburst
PI: Buson
Abstract: PKS 1830-211 is a gravitationally lensed blazar at z~2.5 with two
images at ~1" separation which are well resolved in the two earlier
Chandra HETGS images. Previous observations show strong NH variations
due to variable obscuration in the source. PKS1830 is currently
undergoing its brightest and longest outburst at gamma-rays and
X-rays. INTEGRAL-IBIS gives a 20-50 keV flux of around 6e-11cgs, ~10x
brighter than during the archival Chandra observations. There is short
term variability. We are monitoring the flare with XRT and Fermi, but
these do not resolve the lensed source images. Macro-lensing and
micro-lensing has been detected in this system. The measurement of the
magnification ratio is of special interest given the contradictory
values found with radio and gamma observations. The 3 Chandra
observations of ~20ks each, which should provide spectra that are much
higher SNR than the archival observation, will allow us to determine
NH and the spectral index for both images.
Title : The Origin and Impact of Flares in the Proxima Centauri Planetary
System
PI: MacGregor
Abstract: M dwarfs are the most abundant stars in the galaxy and have a high
frequency of Earth-size planets, making them favored targets of
missions to detect/characterize exoplanets. However, these stars
exhibit high levels of activity, raising questions about the
habitability of their planets. We recently detected a large flare from
Proxima Cen with ALMA (MacGregor et al. 2018) that raises questions
about the relationship between particle acceleration and plasma
heating during flares. To explore this further, we are conducting a
multi-wavelength monitoring campaign of Proxima Cen involving ground-
and space-based facilities. Measuring X-ray flaring energies is
critical, since high energy radiation can erode a planet's atmosphere
by photodissociating water and ozone. We propose to obtain
simultaneous coverage with Chandra to constrain the X-ray properties
of detected flares and their impact on planetary habitability, and to
determine how flaring emission correlates across the EM spectrum.
Title : The Origin and Impact of Flares in the Proxima Centauri Planetary
System
PI: MacGregor
Abstract: M dwarfs are the most abundant stars in the galaxy and have a high
frequency of Earth-size planets, making them favored targets of
missions to detect/characterize exoplanets. However, these stars
exhibit high levels of activity, raising questions about the
habitability of their planets. We recently detected a large flare from
Proxima Cen with ALMA (MacGregor et al. 2018) that raises questions
about the relationship between particle acceleration and plasma
heating during flares. To explore this further, we are conducting a
multi-wavelength monitoring campaign of Proxima Cen involving ground-
and space-based facilities. Measuring X-ray flaring energies is
critical, since high energy radiation can erode a planet's atmosphere
by photodissociating water and ozone. We propose to obtain
simultaneous coverage with Chandra to constrain the X-ray properties
of detected flares and their impact on planetary habitability, and to
determine how flaring emission correlates across the EM spectrum.
Title : Exploring the possible link between mass ejection and X-ray emission
in a nearby TDE
PI: Alexander
Abstract: AT2019ahk is a rare nearby (110 Mpc) candidate tidal disruption event
(TDE) discovered on 29 January 2019. This source was detected
unusually early (1 month before peak optical light), allowing for
excellent constraints on the properties of the disrupting SMBH and
detailed followup with Swift and ground-based facilities. Our ALMA
observations of this event reveal the first detection of mm emission
from an optical TDE, a signpost of mass ejection. XRT reveals the
event to be X-ray faint, with implications for a proposed radio/X-ray
correlation in radio TDEs. Here, we propose Chandra observations to 1)
determine the temporal behavior of the X-ray source and establish a
link to the UV/optical and mm evolution; 2) use Chandra's superior
angular resolution to pinpoint its location and determine whether it
is point-like (as expected for a TDE) or extended. AT2019ahk provides
a unique opportunity to test models of SMBH accretion and to study the
entire lifecycle of a weak SMBH jet.
Title : Exploring the possible link between mass ejection and X-ray emission
in a nearby TDE
PI: Alexander
Abstract: AT2019ahk is a rare nearby (110 Mpc) candidate tidal disruption event
(TDE) discovered on 29 January 2019. This source was detected
unusually early (1 month before peak optical light), allowing for
excellent constraints on the properties of the disrupting SMBH and
detailed followup with Swift and ground-based facilities. Our ALMA
observations of this event reveal the first detection of mm emission
from an optical TDE, a signpost of mass ejection. XRT reveals the
event to be X-ray faint, with implications for a proposed radio/X-ray
correlation in radio TDEs. Here, we propose Chandra observations to 1)
determine the temporal behavior of the X-ray source and establish a
link to the UV/optical and mm evolution; 2) use Chandra's superior
angular resolution to pinpoint its location and determine whether it
is point-like (as expected for a TDE) or extended. AT2019ahk provides
a unique opportunity to test models of SMBH accretion and to study the
entire lifecycle of a weak SMBH jet.
Title : Chandra-HRC Support for Juno-UVS on Attitude Adjustment Perijoves
PI: Gladstone
Abstract: To study the morphology and physics of Jupiter's auroral x-rays,
through comparison with simultaneous Juno-UVS remote sensing and
Juno-JADE and Juno-JEDI in-situ particle observations. The best Juno
data for Jupiter's northern aurora are now obtained during specific
"attitude adjustments" perijoves, which are only scheduled a few
months ahead of time. Jovian auroral x-rays are associated with a
region of UV emission known as the active region, which likely
coincides with the return current connected with the main auroral
oval. Juno-JEDI provides useful measurements of O ion precipitation,
but only along the magnetic footprint of Juno. Simultaneous maps from
Chandra provide highly scientifically useful supporting observations
for Juno.
Title : Determining the X-ray Position of 4U 1901+03
PI: Hemphill
Abstract: Transient X-ray pulsars are excellent laboratories for studying
accretion and binary evolution, due to the large luminosity changes
during an outburst. However, these outbursts are typically infrequent
and aperiodic, often with years or decades between events. For this
reason, many systems are relatively poorly studied. One vital
measurement is the localization of the X-ray source, as this enables
the identification and classification of the optical counterpart, the
donor star, the properties of which are of supreme importance for
understanding the evolution of the system and interpreting the X-ray
spectra and variability of the source. 4U 1901+03 has just begun its
fourth outburst in history, but currently the best position is the
RXTE/PCA 1' error circle, so the optical counterpart is still
unknown.
Title : Extraordinary 9 hours quasi-periodic X-ray outbursts from an accreting
SMBH
PI: Miniutti
Abstract: We have observed the Seyfert galaxy GSN 069 on 2018-12-24 with XMM and
discovered two extraordinary X-ray flares spaced by ~30ks. No flares
were detected back in 2014 during a 80 ks XMM observation. We obtained
a further long XMM DDT on 2019-01-17, and obtained 5 extraordinary
quasi-periodic flares separated by ~32ks. This beaviour is unlike
anything seen before in AGN and potentially represent a Rosetta-stone
for our understanding of SMBH accretion and/or dynamics. GSN 069 is
either a re-activated AGN after a long period of quiescence or
(perhaps more likely) a long-lived Tidal Disruption Event.
Interpretations for the extraordinary observed behaviour include GR
precession of the innermost flow, a very close separation SMBH binary
system etc. We need to use the Chandra current visibility window (no
XMM observation is possible now) to follow-up this extraordinary
system and start to constrain the interpretation. More details in the
uploaded PDF science case.
Title : Revealing the SXP 4.78 transition in to the 'propeller mode'
PI: Lutovinov
Abstract: One of the most straightforward manifestations of the interaction of
matter with the magnetosphere of a neutron star is a transition of the
accreting neutron star to the so-called propeller regime (Illarionov &
Sunyaev 1975), when the accreting matter is stopped by the centrifugal
barrier set up by the rotating magnetosphere. Such a transition is
expected to occur at the limiting luminosity defined by the dipolar
magnetic field strength and rotation rate of the pulsar. Confident
detection of such a transition provides a completely independent
estimate of the magnetic field of the pulsar and in general allows for
a better understanding of the interaction of the accretion flow and
magnetosphere (Tsygankov et. al. 2016). Measured limiting luminosity,
confirmed with the low flux and changed spectrum in SXP 4.78 will be
utilized to determine magnetic field strength, yet unknown for this
system.
Title : Timely Assessment of the X-ray Flux of Newly Discovered Quadruply
Lensed Quasars
PI: Pooley
Abstract: Our previous work has shown the unique power of Chandra observations
of quadruply gravitationally lensed quasars to address several
fundamental astrophysical issues. We have used these observations to
(1) determine the cause of flux ratio anomalies, (2) measure the sizes
of quasar accretion disks, (3) determine the dark matter content of
the lensing galaxies, and (4) measure the stellar mass-to-light ratio
(in fact, this is the only way to measure the stellar mass-to-light
ratio beyond the solar neighborhood). In all cases, the main source of
uncertainty in our results is the small size of the sample of known
quads; only about 15 systems had been available for study with Chandra
unti the past year or two. New, large-area sky surveys have produced a
trove of new quads, and timely Chandra observations will allow for
great progress. We aim to propose such observations in the coming
cycle and seek to assess the unknown X-ray flux now in order to
propose the most efficient GO program.
Title : Timely Assessment of the X-ray Flux of Newly Discovered Quadruply
Lensed Quasars
PI: Pooley
Abstract: Our previous work has shown the unique power of Chandra observations
of quadruply gravitationally lensed quasars to address several
fundamental astrophysical issues. We have used these observations to
(1) determine the cause of flux ratio anomalies, (2) measure the sizes
of quasar accretion disks, (3) determine the dark matter content of
the lensing galaxies, and (4) measure the stellar mass-to-light ratio
(in fact, this is the only way to measure the stellar mass-to-light
ratio beyond the solar neighborhood). In all cases, the main source of
uncertainty in our results is the small size of the sample of known
quads; only about 15 systems had been available for study with Chandra
unti the past year or two. New, large-area sky surveys have produced a
trove of new quads, and timely Chandra observations will allow for
great progress. We aim to propose such observations in the coming
cycle and seek to assess the unknown X-ray flux now in order to
propose the most efficient GO program.
Title : Timely Assessment of the X-ray Flux of Newly Discovered Quadruply
Lensed Quasars
PI: Pooley
Abstract: Our previous work has shown the unique power of Chandra observations
of quadruply gravitationally lensed quasars to address several
fundamental astrophysical issues. We have used these observations to
(1) determine the cause of flux ratio anomalies, (2) measure the sizes
of quasar accretion disks, (3) determine the dark matter content of
the lensing galaxies, and (4) measure the stellar mass-to-light ratio
(in fact, this is the only way to measure the stellar mass-to-light
ratio beyond the solar neighborhood). In all cases, the main source of
uncertainty in our results is the small size of the sample of known
quads; only about 15 systems had been available for study with Chandra
unti the past year or two. New, large-area sky surveys have produced a
trove of new quads, and timely Chandra observations will allow for
great progress. We aim to propose such observations in the coming
cycle and seek to assess the unknown X-ray flux now in order to
propose the most efficient GO program.
Title : Timely Assessment of the X-ray Flux of Newly Discovered Quadruply
Lensed Quasars
PI: Pooley
Abstract: Our previous work has shown the unique power of Chandra observations
of quadruply gravitationally lensed quasars to address several
fundamental astrophysical issues. We have used these observations to
(1) determine the cause of flux ratio anomalies, (2) measure the sizes
of quasar accretion disks, (3) determine the dark matter content of
the lensing galaxies, and (4) measure the stellar mass-to-light ratio
(in fact, this is the only way to measure the stellar mass-to-light
ratio beyond the solar neighborhood). In all cases, the main source of
uncertainty in our results is the small size of the sample of known
quads; only about 15 systems had been available for study with Chandra
unti the past year or two. New, large-area sky surveys have produced a
trove of new quads, and timely Chandra observations will allow for
great progress. We aim to propose such observations in the coming
cycle and seek to assess the unknown X-ray flux now in order to
propose the most efficient GO program.
Title : Timely Assessment of the X-ray Flux of Newly Discovered Quadruply
Lensed Quasars
PI: Pooley
Abstract: Our previous work has shown the unique power of Chandra observations
of quadruply gravitationally lensed quasars to address several
fundamental astrophysical issues. We have used these observations to
(1) determine the cause of flux ratio anomalies, (2) measure the sizes
of quasar accretion disks, (3) determine the dark matter content of
the lensing galaxies, and (4) measure the stellar mass-to-light ratio
(in fact, this is the only way to measure the stellar mass-to-light
ratio beyond the solar neighborhood). In all cases, the main source of
uncertainty in our results is the small size of the sample of known
quads; only about 15 systems had been available for study with Chandra
unti the past year or two. New, large-area sky surveys have produced a
trove of new quads, and timely Chandra observations will allow for
great progress. We aim to propose such observations in the coming
cycle and seek to assess the unknown X-ray flux now in order to
propose the most efficient GO program.
Title : Timely Assessment of the X-ray Flux of Newly Discovered Quadruply
Lensed Quasars
PI: Pooley
Abstract: Our previous work has shown the unique power of Chandra observations
of quadruply gravitationally lensed quasars to address several
fundamental astrophysical issues. We have used these observations to
(1) determine the cause of flux ratio anomalies, (2) measure the sizes
of quasar accretion disks, (3) determine the dark matter content of
the lensing galaxies, and (4) measure the stellar mass-to-light ratio
(in fact, this is the only way to measure the stellar mass-to-light
ratio beyond the solar neighborhood). In all cases, the main source of
uncertainty in our results is the small size of the sample of known
quads; only about 15 systems had been available for study with Chandra
unti the past year or two. New, large-area sky surveys have produced a
trove of new quads, and timely Chandra observations will allow for
great progress. We aim to propose such observations in the coming
cycle and seek to assess the unknown X-ray flux now in order to
propose the most efficient GO program.
Title : Timely Assessment of the X-ray Flux of Newly Discovered Quadruply
Lensed Quasars
PI: Pooley
Abstract: Our previous work has shown the unique power of Chandra observations
of quadruply gravitationally lensed quasars to address several
fundamental astrophysical issues. We have used these observations to
(1) determine the cause of flux ratio anomalies, (2) measure the sizes
of quasar accretion disks, (3) determine the dark matter content of
the lensing galaxies, and (4) measure the stellar mass-to-light ratio
(in fact, this is the only way to measure the stellar mass-to-light
ratio beyond the solar neighborhood). In all cases, the main source of
uncertainty in our results is the small size of the sample of known
quads; only about 15 systems had been available for study with Chandra
unti the past year or two. New, large-area sky surveys have produced a
trove of new quads, and timely Chandra observations will allow for
great progress. We aim to propose such observations in the coming
cycle and seek to assess the unknown X-ray flux now in order to
propose the most efficient GO program.
Title : Timely Assessment of the X-ray Flux of Newly Discovered Quadruply
Lensed Quasars
PI: Pooley
Abstract: Our previous work has shown the unique power of Chandra observations
of quadruply gravitationally lensed quasars to address several
fundamental astrophysical issues. We have used these observations to
(1) determine the cause of flux ratio anomalies, (2) measure the sizes
of quasar accretion disks, (3) determine the dark matter content of
the lensing galaxies, and (4) measure the stellar mass-to-light ratio
(in fact, this is the only way to measure the stellar mass-to-light
ratio beyond the solar neighborhood). In all cases, the main source of
uncertainty in our results is the small size of the sample of known
quads; only about 15 systems had been available for study with Chandra
unti the past year or two. New, large-area sky surveys have produced a
trove of new quads, and timely Chandra observations will allow for
great progress. We aim to propose such observations in the coming
cycle and seek to assess the unknown X-ray flux now in order to
propose the most efficient GO program.
Title : Timely Assessment of the X-ray Flux of Newly Discovered Quadruply
Lensed Quasars
PI: Pooley
Abstract: Our previous work has shown the unique power of Chandra observations
of quadruply gravitationally lensed quasars to address several
fundamental astrophysical issues. We have used these observations to
(1) determine the cause of flux ratio anomalies, (2) measure the sizes
of quasar accretion disks, (3) determine the dark matter content of
the lensing galaxies, and (4) measure the stellar mass-to-light ratio
(in fact, this is the only way to measure the stellar mass-to-light
ratio beyond the solar neighborhood). In all cases, the main source of
uncertainty in our results is the small size of the sample of known
quads; only about 15 systems had been available for study with Chandra
unti the past year or two. New, large-area sky surveys have produced a
trove of new quads, and timely Chandra observations will allow for
great progress. We aim to propose such observations in the coming
cycle and seek to assess the unknown X-ray flux now in order to
propose the most efficient GO program.
Title : A disk event in an Oe star
PI: Rauw
Abstract: Massive stars, including those with decretion disks (i.e. Oe and Be
stars), have an intrinsic X-ray emission linked to shocks in their
unstable winds with kT~0.6keV & log(Lx/Lbol)~-7. However,gamma-Cas
objects, named after their prototype, are substantially X-ray brighter
and emit harder X-rays. The origin of their high-energy emission
remains debated, but our recent observation of HD45314 during a
dissipation of its disk revealed an exceptional event: the X-ray
mission went 'back to normal', underlining the key role of the disk in
this poorly known phenomenon. However, to fully constrain it, the
inverse process (a 'normal' star becoming gamma-Cas) should also be
detected... but it has never been reported before.
Title : A multi-wavelength ATCA/GAIA/Chandra search for the weakest Jets
PI: Reynolds
Abstract: Herein, we propose to obtain a 20ks Chandra imaging spectroscopy
observation of the dynamically confirmed BH GS 1354-64 to occur
quasi-simultaneously with an approved and scheduled ATCA radio
observation. Previous Chandra studies have revealed an anomalous high
luminosity quiescent accretion flow in this source (Reynolds et al.
2011). A new lower distance to the source has been proposed based on
GAIA parallax measurements (Gandhi et al. 2018). This new distance
would resolve the X-ray luminosity issue if the distance is closer to
2 kpc. At the GAIA distance the radio jet is easily within reach by
ATCA. A radio detection will provide valuable information on the
correct distance, and an additional constraint on the radio/X-ray
correlation at the lowest luminosities. Quiescent BHXBs are known to
be highly variable (F_var~60% in both the X-ray and radio), such that
a rigorous interpretation of a radio detection is impossible without
contemporaneous constraints on the X-ray flux.
Title : Verifying a hyperluminous X-ray source in the spectroscopically
studied young starburst ESO 338-IG04
PI: Oskinova
Abstract: The enigmatic hyperluminous X-ray sources (HLXs) are off-nuclear point
sources with Lx> 10^{41} erg/s. HLXs probe different population of
compact objects compared to other accretors, and likely contain
intermediate mass black holes. Only a handful of HLX candidates is
known. The identification of a HLX in a galaxy with well characterized
stellar populations is the key to unlock a range of astrophysical
problems, such as the escape of ionizing radiation, stellar feedback,
double black hole formation, intermediate mass black holes in star
clusters, the lowest AGN masses and luminosities. From XMM images we
found that the low-metallicity starburst galaxy ESO 338-IG04 hosts a
candidate HLX. The stellar population of ESO 338-IG04 is already
thoroughly investigated thanks to the integral field spectroscopy with
MUSE at ESO VLT (Bik et al. 2018 arXiv:1809.03597). Here we seek to
determine the X-ray position of the new HLX and unambiguously identify
its optical counterpart.
Title : Characterizing the X-ray Driven Chemistry of Protoplanetary Disks in
Orion
PI: Cleeves
Abstract: Young stars are surrounded by molecule-rich protoplanetary disks whose
chemistry is expected to evolve slowly, over ~Myr. Hence, we were
surprised to discover variability in H13CO+ J=3-2 emission from the IM
Lup disk between 3 observations taken over one year. This molecule is
X-ray sensitive, and a natural explanation is that stellar X-ray
flares may drive large changes in the disk composition. We have
followed up on a second source, DM Tau, and indeed see variations
consistent with X-ray driven disk chemistry but still lack the
"smoking gun" of an X-ray flare preceding H13CO+ variability. We have
recently obtained Swift and ALMA time to monitor 10 disks in Orion,
and here propose to obtain X-ray spectral shape info with Chandra.
Using simulations, we estimate a 93% probability of seeing H13CO+
variability preceded by an X-ray change for at least one source in our
sample. If confirmed, these observations will be the start of an
entirely new field of time-domain astrochemistry.
Title : Characterizing the X-ray Driven Chemistry of Protoplanetary Disks in
Orion
PI: Cleeves
Abstract: Young stars are surrounded by molecule-rich protoplanetary disks whose
chemistry is expected to evolve slowly, over ~Myr. Hence, we were
surprised to discover variability in H13CO+ J=3-2 emission from the IM
Lup disk between 3 observations taken over one year. This molecule is
X-ray sensitive, and a natural explanation is that stellar X-ray
flares may drive large changes in the disk composition. We have
followed up on a second source, DM Tau, and indeed see variations
consistent with X-ray driven disk chemistry but still lack the
"smoking gun" of an X-ray flare preceding H13CO+ variability. We have
recently obtained Swift and ALMA time to monitor 10 disks in Orion,
and here propose to obtain X-ray spectral shape info with Chandra.
Using simulations, we estimate a 93% probability of seeing H13CO+
variability preceded by an X-ray change for at least one source in our
sample. If confirmed, these observations will be the start of an
entirely new field of time-domain astrochemistry.
Title : Witnessing the Birth of a Blazar
PI: Paliya
Abstract: Gamma-ray detected narrow line Seyfert 1 (g-NLSy1s) galaxies are the
missing link between radio-quiet AGN and blazars. It is tedious to
study the host galaxy environment in blazars due to their jet
dominated emission. Therefore, g-NLSy1s, being lower jet power
objects, are the only beamed AGNs to unravel the jet-host galaxy
interaction. We have imaged the host of a g-NLSy1, TXS 2116-077, with
Subaru telescope and have discovered that the host is in the act of
merging with a nearby faint AGN (sep ~3", https://goo.gl/xdc1nZ).
Theoretically, it has been predicted that most jets are triggered by
mergers but this would be the very first observational evidence of it.
TXS 2116-077, thus, is a rare AGN to verify the theories of the jet
triggering mechanism. Our immediate objectives are: (i) determine the
X-ray morphology of the merging system and perform a spatially
resolved X-ray spectral analysis, and (ii) identify the nature of the
second nucleus (obscured/unobscured).
Title : Target Confirmation for the Great Observatories Accretion Legacy
Survey
PI: Knigge
Abstract: Accretion disks power YSOs, LMXBs, CVs and AGN. The accretion process
often proceeds in bursts, during which systems brighten dramatically.
Remarkably, all transient disk-accretors share common observational
signatures: distinct spectral states, collimated jets, powerful disk
winds and analogous variability. To uncover the universal physics
behind this shared phenomenology, we are planning the Great
Observatories Accretion Legacy Survey. GOALS will observe a
disk-accreting system through a full outburst, with near-continuous
panchromatic coverage from X-ray to radio wavelengths. A viable target
for GOALS must (i) exhibit repeatable outbursts of suitable duration,
and (ii) be bright in all relevant bands. Only transiently accreting
CVs satisfy (i). Satisfying (ii) then requires a CV with detectable
EUV (critical for the soft state in CVs) and radio emission (the only
way to detect jets). Here, we propose a confirm the EUV suitability
(for LETG) of the only viable target we know.
Title : The Compact Remnant in the Extraordinary Type Ib SN 2012au
PI: Patnaude
Abstract: Models of hydrogen-poor and energetic core-collapse supernovae often
invoke engine-driven mechanisms associated with the formation of
compact objects that input energy into the explosion. Determining
whether black holes or neutron stars play key roles in these
explosions remains contentious, as only circumstantial evidence of
their formation can be obtained when the explosion is most luminous. A
recent Magellan IMACS spectrum of the Type Ib SN 2012au revealed the
presence of photoionized, low velocity (2000 km/s) ejecta, with no
evidence for emission from the outer layers of fast moving ejecta. We
hypothesize that the inner layers of ejecta are being energized by a
luminous central source formed during the supernova. X-ray
observations will test this hypothesis. If the optical emission arises
from circumstellar interaction, it should be accompanied by X-rays
from shocked material. A non-detection will strengthen our argument
that the ejecta are energized by a central source.
Title : A possible off-axis GRB in a nearby galaxy
PI: Maccarone
Abstract: This object is a bright X-ray transient in a galaxy at 60 Mpc,
consistent with expectations for a GRB afterglow, but without a GRB
having been seen. Its X-ray spectrum is harder than Gamma=2, but its
X-ray flux is below its optical flux, meaning that these are two
separate components. We thus need to extend the continuum in the
X-rays to get an idea of where the spectral curvature is.
Unfortunately, it cannot be observed by NuSTAR or INTEGRAL right now,
but fortunately it is bright enough to extend down in energy a factor
of 5 by using the LETG. We will also look for emission lines that
might indicate an optically think outflow and absorption lines that
might help characterize its local ISM.
Title : Beyond the Coronal Graveyard
PI: AYRES
Abstract: Iconic Arcturus is member of a populous class of low-mass red giants
whose warm winds are a life-blood of Galactic ecology. How their mass
outflows are powered has remained elusive. A solar-like coronal wind
seemed unlikely, because the red giants have a very low incidence of
high-energy detections. In fact, Arcturus, itself, is one of the
weakest X-ray sources known among the bright cool stars. An intriguing
possibility is that red giants do have significant magnetic activity
and coronae, but mostly hidden beneath their puffy chromospheres.
Unfortunately, the X-ray spectra that could test the "buried corona"
conjecture are beyond reach of contemporary facilities. However, a
new, robust X-ray detection of Arcturus would inform the next
generation of high-energy observatories, whether such advanced
measurements in fact would be feasible.
Title : Probing the duty cycle of a nuclear intermediate mass black hole
accreting at the Eddington limit
PI: Chilingarian
Abstract: Intermediate mass black holes represent (IMBH) a missing block in the
understanding of supermassive black hole assembly. Their very
existence is still debated. Using comprehensive multi-wavelength data
mining we identified 305 IMBH candidates by searching AGN signatures
in optical spectra of 1 million galaxies from SDSS. In 2017 we
followed up two of the candidates with Chandra and detected bright
X-ray emission from one of them, which corresponded to the level close
to the Eddington limit for its mass (70k MSun). This is the least
massive known active central black hole that has an X-ray spectrum.
Here we propose to observe this source once again in order to get the
first insights on the duty cycle of an IMBH-powered AGN. In 10ksec we
expect 500 photons from the source if the luminosity is persistent,
which we suspect is true given the lack of optical variability of the
broad-line component of H-alpha.
Title : Chandra observations of NGC3893: Completion of the Palomar Galaxies
Legacy Sample
PI: McHardy
Abstract: In proposal 18620515 we were awarded observations to complete Chandra
coverage, to 10ks per target, of ALL of the galaxies from the Palomar
bright nearby galaxies sample of Ho et al (1995) in the declination
range +40 to +65. This sample is widely regarded as the statistically
most complete sample of nearby galaxies and is the subject of 'legacy'
surveys in many bands. In particular we made high resolution (0.15
arcsec) eMERLIN radio observations of all the above galaxies, not just
those classed as active, as in other studies. Only Chandra provides
comparable X-ray resolution. Thus we should be able to study
relationships such as the radio/X-ray/BH mass 'fundamental plane', or
derive X-ray luminosity functions at very low luminosities, for
different galaxy types without any concerns regarding incompleteness.
We selected our Chandra sample to avoid duplication and erroneously
removed one galaxy. We here request one 10ks observation to make the
Chandra legacy sample 100% complete.
Title : GW170817: Long term tracking of the the X-ray light curve.
PI: Wilkes
Abstract: This proposal is a merger of several DDT requests to follow-up the
NS-NS merger: GW170817.
Title : Wind energetic and dust scattering halo in Swift J1658.2-4242
PI: Ponti
Abstract: SwiftJ1658.2-4242 is a newly discovered high inclination BH-XRB. We
obtained 5*30ks XMM+NuSTAR+3*30ks AstroSAT campaign following the
evolution of the wind and the accretion systems from the hard to the
soft intermediate state (Feb. 27-Mar. 27). The source shows never-seen
Compton thick dips and a behaviour observed only in few systems and of
unclear origin. This appears as sudden (<50s) drops/increases
(flip-flop) of the flux, with weak colour variations and non-periodic.
A QPO at 6Hz is observed at lower flux and it disappears at high flux.
A variable absorption line at ~7 keV +a relativistic FeK line are
observed to evolve during the outburst. We request a 30ks HETG
observation during the current soft state to: A) Determine the
energetics of the wind, investigate its relations with the states and
flip-flop behaviour; B) Disentangle absorption from relativistic line;
C) Detail the inner parts of the dust scattering halo; D) Determine
the amount of Iron depleted into dust grains.
Title : Zeroing in on the Mass Loss Properties of Core Collapse Supernova
Progenitors
PI: Patnaude
Abstract: The mass loss history of massive stars is one of the least understood
yet fundamental aspects of stellar evolution. How and when do massive
stars shed their hydrogen envelopes? Is there a relationship between
the expulsion of the stellar envelope and core collapse? Is there a
fundamental relationship between late time mass loss and supernova
classification? These central, yet open questions motivate the
proposed Chandra Successor Mission program. In regards to these
questions, studying the evolution of a supernova shock, over
timescales of decades, as it interacts with the ejected envelope of
the progenitor, provides insight into how much mass was lost and
perhaps most importantly, when it was lost, prior to core collapse.
X-ray emission from the shocked gas probes the dynamics of the
interaction, and when combined with multiwavelength observations,
constrains properties of the surrounding circumstellar gas and thus
the later stages of the progenitor's evolution.
Title : GW170817: Long term tracking of the the X-ray light curve.
PI: Wilkes
Abstract: This proposal is a merger of several DDT requests to follow-up the
NS-NS merger: GW170817.
Title : Origin of the X-ray to TeV emission of the M87 AGN
PI: Wong
Abstract: M87 hosts a 3-6 billion solar mass black hole with an exceptional
relativistic jet. It has been regularly monitored in radio to TeV
bands, but little has been done in hard X-rays >10 keV. For the first
time, we have successfully detected hard X-rays up to 40 keV from its
X-ray core with joint Chandra and NuSTAR observations, providing
important insights to the X-ray origins (Wong et al. 2017): from the
unresolved jet or the accretion flow. We found that the hard X-ray
emission is significantly lower than that predicted by synchrotron
self-Compton models introduced to explain emission above a GeV. To
further understand these high energy processes, a key component is to
monitor the soft and hard X-ray emission and study their correlation.
Together with the Event Horizon Telescope, NuSTAR will observe M87 in
April 2018. We propose Chandra snapshots near the NuSTAR window, which
is essential to resolve the keV jet and to pin-point the location of
the high energy active site.
Title : Origin of the X-ray to TeV emission of the M87 AGN
PI: Wong
Abstract: M87 hosts a 3-6 billion solar mass black hole with an exceptional
relativistic jet. It has been regularly monitored in radio to TeV
bands, but little has been done in hard X-rays >10 keV. For the first
time, we have successfully detected hard X-rays up to 40 keV from its
X-ray core with joint Chandra and NuSTAR observations, providing
important insights to the X-ray origins (Wong et al. 2017): from the
unresolved jet or the accretion flow. We found that the hard X-ray
emission is significantly lower than that predicted by synchrotron
self-Compton models introduced to explain emission above a GeV. To
further understand these high energy processes, a key component is to
monitor the soft and hard X-ray emission and study their correlation.
Together with the Event Horizon Telescope, NuSTAR will observe M87 in
April 2018. We propose Chandra snapshots near the NuSTAR window, which
is essential to resolve the keV jet and to pin-point the location of
the high energy active site.
Title : Determining the emission region of VHE gamma-rays in radio galaxy 3C
264
PI: Santander
Abstract: We request DDT observations of the radio galaxy 3C 264, which VERITAS
is currently observing in an active state that has led to its first
detection in VHE gamma-rays. The analysis of the VHE observations is
on-going and VERITAS plans to perform a deep exposure of the object
over the coming days. This detection would represent the 6th radio
galaxy observed in VHE gamma rays. Radio galaxies are currently the
only non-blazar AGN detected in this band. As the jet of 3C 264 has
been resolved by Chandra, this detection presents a unique opportunity
to determine the location of the VHE gamma-ray emission region and
differentiate its origin with the core and inner jet, or the outer
resolved jet. A MWL campaign is being organized for the source.
Title : MAPPING OUT THE EXPLOSIVE MASS-LOSS HISTORY OF THE IMPOSSIBLE SN
iPTF14hls
PI: MARGUTTI
Abstract: The stellar explosion iPTF14hls has been confusing the community for a
while, with a spectral and temporal evolution that could not be
reconciled under standard scenarios. However, iPTF14hls recently
experienced a complete spectral metamorphosis. This evolution suggests
that the solution to the puzzle might be the interaction of the
blastwave with an environment sculpted by the progenitor's eruptions
before the final explosion. If this is correct, iPTF14hls should
produce rising X-ray and radio emission in the next months. Here we
ask for CXO monitoring to test our interacting scenario.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : LOW SURFACE BRIGHTNESS GALAXIES AND THE BLACK HOLE OCCUPATION
FRACTION
PI: Gallo
Abstract: We propose a snapshot survey of nearby low-surface brightness galaxies
(unbiased with respect to nuclear properties) to measure the rate and
incidence of low Eddington ratio nuclear X-ray emission and determine
how the nuclear L_X to mass (stellar and/or gas) relation in this
sample compares with that of normal, high surface brightness galaxies.
Results from this program will inform the galaxy selection function
needed towards a high accuracy black hole occupation fraction
measurement with Lynx. In turn, this will constrain the primary mode
for black hole seeding at high z, complementing efforts that will be
undertaken at high-z.
Title : Zeroing in on the Mass Loss Properties of Core Collapse Supernova
Progenitors
PI: Patnaude
Abstract: The mass loss history of massive stars is one of the least understood
yet fundamental aspects of stellar evolution. How and when do massive
stars shed their hydrogen envelopes? Is there a relationship between
the expulsion of the stellar envelope and core collapse? Is there a
fundamental relationship between late time mass loss and supernova
classification? These central, yet open questions motivate the
proposed Chandra Successor Mission program. In regards to these
questions, studying the evolution of a supernova shock, over
timescales of decades, as it interacts with the ejected envelope of
the progenitor, provides insight into how much mass was lost and
perhaps most importantly, when it was lost, prior to core collapse.
X-ray emission from the shocked gas probes the dynamics of the
interaction, and when combined with multiwavelength observations,
constrains properties of the surrounding circumstellar gas and thus
the later stages of the progenitor's evolution.
Title : Zeroing in on the Mass Loss Properties of Core Collapse Supernova
Progenitors
PI: Patnaude
Abstract: The mass loss history of massive stars is one of the least understood
yet fundamental aspects of stellar evolution. How and when do massive
stars shed their hydrogen envelopes? Is there a relationship between
the expulsion of the stellar envelope and core collapse? Is there a
fundamental relationship between late time mass loss and supernova
classification? These central, yet open questions motivate the
proposed Chandra Successor Mission program. In regards to these
questions, studying the evolution of a supernova shock, over
timescales of decades, as it interacts with the ejected envelope of
the progenitor, provides insight into how much mass was lost and
perhaps most importantly, when it was lost, prior to core collapse.
X-ray emission from the shocked gas probes the dynamics of the
interaction, and when combined with multiwavelength observations,
constrains properties of the surrounding circumstellar gas and thus
the later stages of the progenitor's evolution.
Title : Zeroing in on the Mass Loss Properties of Core Collapse Supernova
Progenitors
PI: Patnaude
Abstract: The mass loss history of massive stars is one of the least understood
yet fundamental aspects of stellar evolution. How and when do massive
stars shed their hydrogen envelopes? Is there a relationship between
the expulsion of the stellar envelope and core collapse? Is there a
fundamental relationship between late time mass loss and supernova
classification? These central, yet open questions motivate the
proposed Chandra Successor Mission program. In regards to these
questions, studying the evolution of a supernova shock, over
timescales of decades, as it interacts with the ejected envelope of
the progenitor, provides insight into how much mass was lost and
perhaps most importantly, when it was lost, prior to core collapse.
X-ray emission from the shocked gas probes the dynamics of the
interaction, and when combined with multiwavelength observations,
constrains properties of the surrounding circumstellar gas and thus
the later stages of the progenitor's evolution.
Title : Zeroing in on the Mass Loss Properties of Core Collapse Supernova
Progenitors
PI: Patnaude
Abstract: The mass loss history of massive stars is one of the least understood
yet fundamental aspects of stellar evolution. How and when do massive
stars shed their hydrogen envelopes? Is there a relationship between
the expulsion of the stellar envelope and core collapse? Is there a
fundamental relationship between late time mass loss and supernova
classification? These central, yet open questions motivate the
proposed Chandra Successor Mission program. In regards to these
questions, studying the evolution of a supernova shock, over
timescales of decades, as it interacts with the ejected envelope of
the progenitor, provides insight into how much mass was lost and
perhaps most importantly, when it was lost, prior to core collapse.
X-ray emission from the shocked gas probes the dynamics of the
interaction, and when combined with multiwavelength observations,
constrains properties of the surrounding circumstellar gas and thus
the later stages of the progenitor's evolution.
Title : Zeroing in on the Mass Loss Properties of Core Collapse Supernova
Progenitors
PI: Patnaude
Abstract: The mass loss history of massive stars is one of the least understood
yet fundamental aspects of stellar evolution. How and when do massive
stars shed their hydrogen envelopes? Is there a relationship between
the expulsion of the stellar envelope and core collapse? Is there a
fundamental relationship between late time mass loss and supernova
classification? These central, yet open questions motivate the
proposed Chandra Successor Mission program. In regards to these
questions, studying the evolution of a supernova shock, over
timescales of decades, as it interacts with the ejected envelope of
the progenitor, provides insight into how much mass was lost and
perhaps most importantly, when it was lost, prior to core collapse.
X-ray emission from the shocked gas probes the dynamics of the
interaction, and when combined with multiwavelength observations,
constrains properties of the surrounding circumstellar gas and thus
the later stages of the progenitor's evolution.
Title : Zeroing in on the Mass Loss Properties of Core Collapse Supernova
Progenitors
PI: Patnaude
Abstract: The mass loss history of massive stars is one of the least understood
yet fundamental aspects of stellar evolution. How and when do massive
stars shed their hydrogen envelopes? Is there a relationship between
the expulsion of the stellar envelope and core collapse? Is there a
fundamental relationship between late time mass loss and supernova
classification? These central, yet open questions motivate the
proposed Chandra Successor Mission program. In regards to these
questions, studying the evolution of a supernova shock, over
timescales of decades, as it interacts with the ejected envelope of
the progenitor, provides insight into how much mass was lost and
perhaps most importantly, when it was lost, prior to core collapse.
X-ray emission from the shocked gas probes the dynamics of the
interaction, and when combined with multiwavelength observations,
constrains properties of the surrounding circumstellar gas and thus
the later stages of the progenitor's evolution.
Title : Zeroing in on the Mass Loss Properties of Core Collapse Supernova
Progenitors
PI: Patnaude
Abstract: The mass loss history of massive stars is one of the least understood
yet fundamental aspects of stellar evolution. How and when do massive
stars shed their hydrogen envelopes? Is there a relationship between
the expulsion of the stellar envelope and core collapse? Is there a
fundamental relationship between late time mass loss and supernova
classification? These central, yet open questions motivate the
proposed Chandra Successor Mission program. In regards to these
questions, studying the evolution of a supernova shock, over
timescales of decades, as it interacts with the ejected envelope of
the progenitor, provides insight into how much mass was lost and
perhaps most importantly, when it was lost, prior to core collapse.
X-ray emission from the shocked gas probes the dynamics of the
interaction, and when combined with multiwavelength observations,
constrains properties of the surrounding circumstellar gas and thus
the later stages of the progenitor's evolution.
Title : Zeroing in on the Mass Loss Properties of Core Collapse Supernova
Progenitors
PI: Patnaude
Abstract: The mass loss history of massive stars is one of the least understood
yet fundamental aspects of stellar evolution. How and when do massive
stars shed their hydrogen envelopes? Is there a relationship between
the expulsion of the stellar envelope and core collapse? Is there a
fundamental relationship between late time mass loss and supernova
classification? These central, yet open questions motivate the
proposed Chandra Successor Mission program. In regards to these
questions, studying the evolution of a supernova shock, over
timescales of decades, as it interacts with the ejected envelope of
the progenitor, provides insight into how much mass was lost and
perhaps most importantly, when it was lost, prior to core collapse.
X-ray emission from the shocked gas probes the dynamics of the
interaction, and when combined with multiwavelength observations,
constrains properties of the surrounding circumstellar gas and thus
the later stages of the progenitor's evolution.
Title : Zeroing in on the Mass Loss Properties of Core Collapse Supernova
Progenitors
PI: Patnaude
Abstract: The mass loss history of massive stars is one of the least understood
yet fundamental aspects of stellar evolution. How and when do massive
stars shed their hydrogen envelopes? Is there a relationship between
the expulsion of the stellar envelope and core collapse? Is there a
fundamental relationship between late time mass loss and supernova
classification? These central, yet open questions motivate the
proposed Chandra Successor Mission program. In regards to these
questions, studying the evolution of a supernova shock, over
timescales of decades, as it interacts with the ejected envelope of
the progenitor, provides insight into how much mass was lost and
perhaps most importantly, when it was lost, prior to core collapse.
X-ray emission from the shocked gas probes the dynamics of the
interaction, and when combined with multiwavelength observations,
constrains properties of the surrounding circumstellar gas and thus
the later stages of the progenitor's evolution.
Title : Beyond the Coronal Graveyard
PI: AYRES
Abstract: Iconic Arcturus is member of a populous class of low-mass red giants
whose warm winds are a life-blood of Galactic ecology. How their mass
outflows are powered has remained elusive. A solar-like coronal wind
seemed unlikely, because the red giants have a very low incidence of
high-energy detections. In fact, Arcturus, itself, is one of the
weakest X-ray sources known among the bright cool stars. An intriguing
possibility is that red giants do have significant magnetic activity
and coronae, but mostly hidden beneath their puffy chromospheres.
Unfortunately, the X-ray spectra that could test the "buried corona"
conjecture are beyond reach of contemporary facilities. However, a
new, robust X-ray detection of Arcturus would inform the next
generation of high-energy observatories, whether such advanced
measurements in fact would be feasible.
Title : Killing two birds in NGC 5907 with one stone: possible dust scattering
halo in ULX1 and the newly discovered ULX2
PI: Pintore
Abstract: NGC 5907 contains two transient ULXs (separated by 28"), with ULX1
being the most extreme ULX pulsar. In the last Chandra observation,
ULX1 was weak (Lx~2e38 erg/s) and surrounded by diffuse X-ray emission
of radius ~3". It could be a scattering halo from dust in NGC 5907 of
the previous ULX1 high state. This can be proved by observing the flux
decrease expected in this case. A negative result is still interesting
since this would be the only ULX with a persistent X-ray nebula. We
discovered ULX2 at a peak luminosity of ~6e39 erg/s, with a multicolor
blackbody disc spectrum, reminiscent of the soft state of Galactic
accreting black holes (BHs). Hence ULX2 may possibly host a 30 Msun BH
accreting at <= Eddington rates. The source is now decaying below the
ULX regime and, if correctly interpreted, we expect a spectral
transition to a hard powerlaw spectral shape. The current state of the
two targets gives the opportunity to achieve both goals with a single
Chandra observation.
Title : Killing two birds in NGC 5907 with one stone: possible dust scattering
halo in ULX1 and the newly discovered ULX2
PI: Pintore
Abstract: NGC 5907 contains two transient ULXs (separated by 28"), with ULX1
being the most extreme ULX pulsar. In the last Chandra observation,
ULX1 was weak (Lx~2e38 erg/s) and surrounded by diffuse X-ray emission
of radius ~3". It could be a scattering halo from dust in NGC 5907 of
the previous ULX1 high state. This can be proved by observing the flux
decrease expected in this case. A negative result is still interesting
since this would be the only ULX with a persistent X-ray nebula. We
discovered ULX2 at a peak luminosity of ~6e39 erg/s, with a multicolor
blackbody disc spectrum, reminiscent of the soft state of Galactic
accreting black holes (BHs). Hence ULX2 may possibly host a 30 Msun BH
accreting at <= Eddington rates. The source is now decaying below the
ULX regime and, if correctly interpreted, we expect a spectral
transition to a hard powerlaw spectral shape. The current state of the
two targets gives the opportunity to achieve both goals with a single
Chandra observation.
Title : Alpha Centauri: Mind the Gap!
PI: AYRES
Abstract: Cycle 19 proposal to continue long-term monitoring of coronal X-ray
activity cycles of sunlike Alpha Centauri A (G2V) and B (K1V) was not
approved. New Cycle 20 request will address panel's concerns. Even if
Cycle 20 proposal is approved, still will be unpleasant gap in the
semi-annual coverage, ongoing since 2005. Long-term HRC X-ray series
on AlpCen is unique, fundamentally important: key contribution of
Chandra to understanding cycling "Dynamos" of late-type stars, high
scientific priority in solar-stellar physics. Although stellar cycles
are known from CaII monitoring, X-rays contribute uniquely owing to
50X larger contrast at high-energies. A 5 ks pointing in mid-2018
would fill the gap. In fact, most recent AlpCen-A L_X (Ayres: 2018,
RNAAS) shows a possible, unusual, rapid downturn, in the declining
phase of its cycle (previous decline 2001-05 missed by lack of
observations). Only Chandra can resolve AB at present.
Title : Measure spin-up of NGC 300 ULX-1
PI: Vasilopoulos
Abstract: NGC 300 ULX-1 is a newly identified ULX pulsar. The system has shown a
extraordinary spin up rate within the last year, when it spun-up from
31 sec to 20 sec. We request 2x10 ks chandra observations separated by
2-4 days in order to accurately measure the spin up rate of the
pulsar.
Title : Measure spin-up of NGC 300 ULX-1
PI: Vasilopoulos
Abstract: NGC 300 ULX-1 is a newly identified ULX pulsar. The system has shown a
extraordinary spin up rate within the last year, when it spun-up from
31 sec to 20 sec. We request 2x10 ks chandra observations separated by
2-4 days in order to accurately measure the spin up rate of the
pulsar.
Title : GW170817: Tracking the X-ray light curve to study the origin of the
emission
PI: Wilkes
Abstract: Continued tracking of the light curve of this unique NS-NS merger to
understand the emission mechanisms and the structure. We will include
the proposing DDT teams as co-Is on this proposal. They will all have
access to the data, but this proposal does not require that they work
together.
Title : GW170817: Tracking the X-ray light curve to study the origin of the
emission
PI: Wilkes
Abstract: Continued tracking of the light curve of this unique NS-NS merger to
understand the emission mechanisms and the structure. We will include
the proposing DDT teams as co-Is on this proposal. They will all have
access to the data, but this proposal does not require that they work
together.
Title : GW170817: Tracking the X-ray light curve to study the origin of the
emission
PI: Wilkes
Abstract: Continued tracking of the light curve of this unique NS-NS merger to
understand the emission mechanisms and the structure. We will include
the proposing DDT teams as co-Is on this proposal. They will all have
access to the data, but this proposal does not require that they work
together.
Title : GW170817: Tracking the X-ray light curve to study the origin of the
emission
PI: Wilkes
Abstract: Continued tracking of the light curve of this unique NS-NS merger to
understand the emission mechanisms and the structure. We will include
the proposing DDT teams as co-Is on this proposal. They will all have
access to the data, but this proposal does not require that they work
together.
Title : GW170817: Tracking the X-ray light curve to study the origin of the
emission
PI: Wilkes
Abstract: Continued tracking of the light curve of this unique NS-NS merger to
understand the emission mechanisms and the structure. We will include
the proposing DDT teams as co-Is on this proposal. They will all have
access to the data, but this proposal does not require that they work
together.
Title : Detecting X-ray emission from a very massive black hole binary
PI: Liu
Abstract: Our most recent work with LAMOST spectroscopic survey has revealed a
black hole candidate with a B companion, which can be more massive
than 40 solar masses judging from the relative motion of the B
companion (from its absorption lines, with a radial velocity
semi-amplitude of 50km/s) and the black hole (from its broad strong
Halpha emission line, with a semi-amplitude below 10km/s). About 20
LAMOST low resolution spectra taken in two years have revealed its
binarity with a period of 70 days, and GAIA data also confirms its
binarity independently. We have launched a GTC/OSIRIS campaign to take
20 spectra in two months, and a Keck/HIRESr campaign to take 18
spectra in two months, to fine sample its 70-day period and better
determine the binary properties. . Here we propose a 10ksec Chandra
exposure to detect its X-ray emission.
Title : The X-rays of a bright QSO well within the epoch of reionization at
z=7.54
PI: Banados
Abstract: After almost a decade of intense search, our team has finally
discovered a bright QSO well within the epoch of reionization, at
z=7.54. This is by far the most distant QSO known (previous record:
7.08), at a cosmic age of 690 Myr, i.e., only 5% of our universe's
current age. This is the first QSO whose spectrum shows clear evidence
of an intergalactic medium that is >20% neutral and that reionization
is underway. We propose Chandra observations of this unique object to
(i) probe evolution of the X-ray-to-optical luminosity ratio
(alpha-ox) to the highest accessible redshift; (ii) provide a more
reliable estimate of the QSO's bolometric luminosity, and (iii) assess
the feasibility of deeper Chandra and XMM observations for the
upcoming cycles, which would allow us to test whether the first black
holes are accreting at super-Eddington rates.
Title : Characterizing X-ray driven molecular chemistry in a young
protoplanetary disk
PI: Cleeves
Abstract: Young (Myr-old) stars are both X-ray luminous and variable.
Surrounding the star is a molecule-rich protoplanetary disk whose
chemistry is expected to evolve slowly, over $\sim0.01-1$ Myr. In this
context, ALMA provided a curious puzzle when we discovered short-term
variability in the H13CO+ J=3-2 line across three observations of a
disk taken over just a single year (Cleeves et al. 2017). One
explanation is stellar X-ray activity perturbing the chemical ``steady
state'' of the disk, where HCO+ is a known X-ray sensitive molecule
(Cleeves et al. 2014). We were recently awarded SMA time to test the
X-ray driven variability hypothesis (one observation every 6-7 days
for 2 months) by measuring the magnitude and frequency of H13CO+
variability. We propose here to compliment these SMA observations with
Chandra monitoring to directly connect for the first time the
time-varying X-ray state of the star to the composition of the
planet-forming disk.
Title : Characterizing X-ray driven molecular chemistry in a young
protoplanetary disk
PI: Cleeves
Abstract: Young (Myr-old) stars are both X-ray luminous and variable.
Surrounding the star is a molecule-rich protoplanetary disk whose
chemistry is expected to evolve slowly, over $\sim0.01-1$ Myr. In this
context, ALMA provided a curious puzzle when we discovered short-term
variability in the H13CO+ J=3-2 line across three observations of a
disk taken over just a single year (Cleeves et al. 2017). One
explanation is stellar X-ray activity perturbing the chemical ``steady
state'' of the disk, where HCO+ is a known X-ray sensitive molecule
(Cleeves et al. 2014). We were recently awarded SMA time to test the
X-ray driven variability hypothesis (one observation every 6-7 days
for 2 months) by measuring the magnitude and frequency of H13CO+
variability. We propose here to compliment these SMA observations with
Chandra monitoring to directly connect for the first time the
time-varying X-ray state of the star to the composition of the
planet-forming disk.
Title : Characterizing X-ray driven molecular chemistry in a young
protoplanetary disk
PI: Cleeves
Abstract: Young (Myr-old) stars are both X-ray luminous and variable.
Surrounding the star is a molecule-rich protoplanetary disk whose
chemistry is expected to evolve slowly, over $\sim0.01-1$ Myr. In this
context, ALMA provided a curious puzzle when we discovered short-term
variability in the H13CO+ J=3-2 line across three observations of a
disk taken over just a single year (Cleeves et al. 2017). One
explanation is stellar X-ray activity perturbing the chemical ``steady
state'' of the disk, where HCO+ is a known X-ray sensitive molecule
(Cleeves et al. 2014). We were recently awarded SMA time to test the
X-ray driven variability hypothesis (one observation every 6-7 days
for 2 months) by measuring the magnitude and frequency of H13CO+
variability. We propose here to compliment these SMA observations with
Chandra monitoring to directly connect for the first time the
time-varying X-ray state of the star to the composition of the
planet-forming disk.
Title : Characterizing X-ray driven molecular chemistry in a young
protoplanetary disk
PI: Cleeves
Abstract: Young (Myr-old) stars are both X-ray luminous and variable.
Surrounding the star is a molecule-rich protoplanetary disk whose
chemistry is expected to evolve slowly, over $\sim0.01-1$ Myr. In this
context, ALMA provided a curious puzzle when we discovered short-term
variability in the H13CO+ J=3-2 line across three observations of a
disk taken over just a single year (Cleeves et al. 2017). One
explanation is stellar X-ray activity perturbing the chemical ``steady
state'' of the disk, where HCO+ is a known X-ray sensitive molecule
(Cleeves et al. 2014). We were recently awarded SMA time to test the
X-ray driven variability hypothesis (one observation every 6-7 days
for 2 months) by measuring the magnitude and frequency of H13CO+
variability. We propose here to compliment these SMA observations with
Chandra monitoring to directly connect for the first time the
time-varying X-ray state of the star to the composition of the
planet-forming disk.
Title : Characterizing X-ray driven molecular chemistry in a young
protoplanetary disk
PI: Cleeves
Abstract: Young (Myr-old) stars are both X-ray luminous and variable.
Surrounding the star is a molecule-rich protoplanetary disk whose
chemistry is expected to evolve slowly, over $\sim0.01-1$ Myr. In this
context, ALMA provided a curious puzzle when we discovered short-term
variability in the H13CO+ J=3-2 line across three observations of a
disk taken over just a single year (Cleeves et al. 2017). One
explanation is stellar X-ray activity perturbing the chemical ``steady
state'' of the disk, where HCO+ is a known X-ray sensitive molecule
(Cleeves et al. 2014). We were recently awarded SMA time to test the
X-ray driven variability hypothesis (one observation every 6-7 days
for 2 months) by measuring the magnitude and frequency of H13CO+
variability. We propose here to compliment these SMA observations with
Chandra monitoring to directly connect for the first time the
time-varying X-ray state of the star to the composition of the
planet-forming disk.
Title : Characterizing X-ray driven molecular chemistry in a young
protoplanetary disk
PI: Cleeves
Abstract: Young (Myr-old) stars are both X-ray luminous and variable.
Surrounding the star is a molecule-rich protoplanetary disk whose
chemistry is expected to evolve slowly, over $\sim0.01-1$ Myr. In this
context, ALMA provided a curious puzzle when we discovered short-term
variability in the H13CO+ J=3-2 line across three observations of a
disk taken over just a single year (Cleeves et al. 2017). One
explanation is stellar X-ray activity perturbing the chemical ``steady
state'' of the disk, where HCO+ is a known X-ray sensitive molecule
(Cleeves et al. 2014). We were recently awarded SMA time to test the
X-ray driven variability hypothesis (one observation every 6-7 days
for 2 months) by measuring the magnitude and frequency of H13CO+
variability. We propose here to compliment these SMA observations with
Chandra monitoring to directly connect for the first time the
time-varying X-ray state of the star to the composition of the
planet-forming disk.
Title : Characterizing X-ray driven molecular chemistry in a young
protoplanetary disk
PI: Cleeves
Abstract: Young (Myr-old) stars are both X-ray luminous and variable.
Surrounding the star is a molecule-rich protoplanetary disk whose
chemistry is expected to evolve slowly, over $\sim0.01-1$ Myr. In this
context, ALMA provided a curious puzzle when we discovered short-term
variability in the H13CO+ J=3-2 line across three observations of a
disk taken over just a single year (Cleeves et al. 2017). One
explanation is stellar X-ray activity perturbing the chemical ``steady
state'' of the disk, where HCO+ is a known X-ray sensitive molecule
(Cleeves et al. 2014). We were recently awarded SMA time to test the
X-ray driven variability hypothesis (one observation every 6-7 days
for 2 months) by measuring the magnitude and frequency of H13CO+
variability. We propose here to compliment these SMA observations with
Chandra monitoring to directly connect for the first time the
time-varying X-ray state of the star to the composition of the
planet-forming disk.
Title : GW170817: Tracking the X-ray light curve to study the origin of the
emission
PI: Wilkes
Abstract: This proposal is a merger of several DDT requests to follow-up the
NS-NS merger: GW170817 as it comes out of sunblock. We will include
the proposing DDT teams as co-Is on this proposal. They will all have
access to the data, but this proposal does not require that they work
together.
Title : GW170817: Tracking the X-ray light curve to study the origin of the
emission
PI: Wilkes
Abstract: This proposal is a merger of several DDT requests to follow-up the
NS-NS merger: GW170817 as it comes out of sunblock. We will include
the proposing DDT teams as co-Is on this proposal. They will all have
access to the data, but this proposal does not require that they work
together.
Title : Searching for outflows from a nearby super-Eddington accreting neutron
star
PI: Degenaar
Abstract: Swift J0243.6+6124 is a newly discovered Be/X-ray binary that harbours
a 9.8-s pulsar and went into outburst 30 days ago (ATel #10809). It
has been brightening since and reached super-Eddington luminosities on
Nov 1 (Lx~4E38 erg/s), which have been sustained since then (Lx~E39
erg/s on Nov 6). Accretion at super-Eddington rates is predicted to be
associated with strong outflows, both jets and disk winds. Testing
this idea is challenging because super-Eddington accreting neutron
stars are located in other galaxies. However, Swift J0243.6+6124 is
located at a distance of only 4 kpc (Doroshenko et al. 2017,
arXiv:1710.10912). This provides a unique opportunity to study
outflows in the super-Eddington accretion regime. We have secured VLA
radio observations (PI van den Eijnden) to search for a jet. Here, we
request Chandra/HETG observations to look for highly blue-shifted,
ionized absorption features at high (>5 keV) energy that would reveal
a disk wind.
Title : The most distant X-ray luminous cluster discovered by ROSAT
PI: Ebeling
Abstract: We propose a short ACIS-I observation of eMACSJ0324, the most distant
massive cluster discovered to date by ROSAT, confirmed in Sep 2017 to
be at z=0.901 (8 redshifts). At 1.4e^45 erg/s (0.1-2.4 keV), our
target is as X-ray luminous as the giant galaxy clusters (and HFF
targets) MACSJ0416, MACSJ1149, or MACSJ0717 - but at twice the
redshift. If eMACSJ0324 is confirmed to be as massive as its more
nearby, famous siblings (its present X-ray luminosity estimate is
based on 10 RASS photons), it would be one of fewer than a handful
exceptionally massive clusters known at z~1, the first extreme mass
concentrations (>1e^15 M_sun) to decouple from the Hubble flow. Our
DDT request, complemented by an HST Cycle 25 Mid-Cycle proposal, aims
to use Chandra's unparalleled resolution to constrain the contribution
from any point sources to the X-ray flux of eMACSJ0324 as observed in
the RASS, and to obtain a robust measurement of the cluster's total
X-ray luminosity from about 1500 net photons.
Title : Uranus During an Interplanetary Coronal Mass Ejection
PI: Dunn
Abstract: While Jupiter's X-ray Aurora was first detected by the Einstein
Observatory, it remains unknown what processes allow it to create the
energies required for soft X-ray Aurorae. Saturn does not produce
detectable X-ray Aurora. Why these 2 rapidly rotating giant planets,
with internal plasma sources, have such different auroral intensities
remains unclear. Saturn's magnetic field is parallel to its rotation
axis, but Jupiter's has a 10-degree tilt, which helps produce large
electric fields. Uranus' magnetic field is at 60 degrees to the
rotation axis, producing ever-varying magnetospheric dynamics and
reconnection. Given that reconnection is the common explanation for
Jupiter's X-ray Aurora, the extent/absence of X-ray Aurora at Uranus
would show the importance of reconnection as a driver. On 10 Nov, an
ICME arrives at Uranus, which will compress the magnetosphere,
increasing reconnection rates. At Jupiter, ICMEs increase X-ray
auroral counts by a factor of 3-6, improving detectability.
Title : Uranus During an Interplanetary Coronal Mass Ejection
PI: Dunn
Abstract: While Jupiter's X-ray Aurora was first detected by the Einstein
Observatory, it remains unknown what processes allow it to create the
energies required for soft X-ray Aurorae. Saturn does not produce
detectable X-ray Aurora. Why these 2 rapidly rotating giant planets,
with internal plasma sources, have such different auroral intensities
remains unclear. Saturn's magnetic field is parallel to its rotation
axis, but Jupiter's has a 10-degree tilt, which helps produce large
electric fields. Uranus' magnetic field is at 60 degrees to the
rotation axis, producing ever-varying magnetospheric dynamics and
reconnection. Given that reconnection is the common explanation for
Jupiter's X-ray Aurora, the extent/absence of X-ray Aurora at Uranus
would show the importance of reconnection as a driver. On 10 Nov, an
ICME arrives at Uranus, which will compress the magnetosphere,
increasing reconnection rates. At Jupiter, ICMEs increase X-ray
auroral counts by a factor of 3-6, improving detectability.
Title : Candidate TDE AT 2017gbl
PI: Heikkila
Abstract: We discovered a very likely Tidal Disruption Event (TDE) AT 2017gbl in
the luminous infrared galaxy (LIRG) IRAS 23436+5257 (ATels 10651,
10712), which are very rare events. The recent discovery of another
TDE candidate in the LIRG F01004-2237 suggests that there is an
enhanced rate of TDEs in LIRGs which would often be missed due to the
large amounts of gas and dust. TDEs can also be extremely bright in
X-rays. We observed AT 2017gbl with Swift, with no source detected and
with upper limit ~4*10^41 erg/s. LIRGs also host a population of X-ray
binaries, and the X-ray luminosity from the host can be estimated from
the IR-luminosity, at least ~ 5*10^40 erg/s in the case of IRAS
23436+5257. By observing down to this limit, we will put strict
constrains on the intrinsic luminosity of the transient, determining
its nature. In addition, this would be the first direct X-ray
detection of IRAS 23436+5257 and important eg. for studying the
SFR-X-ray luminosity relationship in distant LIRGs.
Title : Probing the Low State of the Most Extreme ULX Pulsar
PI: belfiore
Abstract: The 3 Ultraluminous X-ray Sources (ULXs) driven by accreting neutron
stars well beyond their Eddington limit (L(Edd)) deserve more
investigation as they constrain accretion in a regime that eludes
simple explanations. They all display superorbital flux modulations
and rarely enter a low state not yet understood, that could shed light
on their physics. The sources could go sub-Eddington, or the
centrifugal push could inhibit accretion (propeller effect), or the
pulsar could be obscured by optically thick material (in a disk or
winds). The most extreme ULX pulsar is NGC 5907 ULX (Israel et al
2017, I17), at 500 times L(Edd). Current observational campaigns with
Swift, XMM-Newton, and NuSTAR have recently seen it entering a low
state (<20 L(Edd)) and no recovery after one superorbital period. Now
only Chandra can probe its low flux, resolving it from other sources
in its galaxy (I17, fig S1; Walton et al 2015), and distinguish a
propeller state (~2 L(Edd)) from other scenarios.
Title : X-ray monitoring of GRB170817A
PI: Troja
Abstract: GRB170817A is an under-luminous short GRB possibly located at 40 Mpc
and associated to the peculiar infrared/optical transient SSS17a. Deep
upper limits constrain the presence of an on-axis afterglow. Here we
propose to search for X-ray emission at late times in order to
constrain the presence of an off-axis afterglow and isotropic
electromagnetic counterparts. Due to the proximity to another X-ray
source and the expected faintness of the afterglow fluxes, only the
accuracy and sensitivity of Chandra will allow us to detect the X-ray
counterpart.
Title : The late outburst evolution of Nova Lup 2016: a likely solution of
nova 'mysteries'
PI: Orio
Abstract: The decline of Nova Lup 2016 in the supersoft X-ray phase is occurring
more slowly than in most novae, allowing scheduling during a poorly
known phase, important for the models. The nova has been observed at
maximum with XMM and the PI has kindly shared his data; it is now
monitored with Swift. A Chandra LETG exposure would allow: 1) Precise
determination of N(H), differentiating between cooling and spectral
softening due to diminishing intrinsic absorption; 2) Witnessing
whether turn-off is occurring with decreasing flux at almost constant
T(eff) (implying a shrinking, but still hot surface region), as
inferred in some magnetic novae at the beginning of the decline or in
the early quiescence, or whether the WD is isotropically cooling; 3)
Observing whether the residual wind from the compact WD ceases before
the burning is turned off; 4) Measuring absorption and emission lines
due to transitions of intermediate mass ions, constraining chemical
evolution.
Title : Deep X-ray follow-up of a TDE candidate
PI: Nicholl
Abstract: The transient PS17dhz shows optical signatures typical of tidal
disruption events (TDEs), including blackbody temperature >30000 K and
broad He II emission. However, the host is unusual: a compact galaxy
with absolute magnitude M_r ~ -18, suggesting that PS17dhz may have a
smaller black hole mass than other TDEs. From Swift data we have found
an optical flux F_opt ~ 10^-13 erg/s/cm2, and an X-ray limit F_X <
10^-13 erg/s/cm2. All optical TDEs with X-ray detections have had
X-ray to optical ratios >~ 1, suggesting that PS17dhz is X-ray faint.
However, there are UV/optical TDEs without X-ray detections ( veiled
TDEs). The lack of X-rays could be due to additional
reprocessing/obscuration around the black hole. The Swift
non-detection suggests that PS17dhz is veiled, but since the Swift
X-ray limit is already close to L_opt, a deeper observation with
Chandra gives one of the best chances to detect weak X-rays from a
veiled TDE.
Title : Precise localization of the ultra long high-energy transient
GRB170714A
PI: Troja
Abstract: GRB170714A is a peculiar high-energy transient of ultra-long (>1,000
s) duration. Its nature is still unclear: its high-energy properties
suggest that it could be a relativistic tidal disruption event or a
rare ultralong GRB, produced by an exotic stellar progenitor. Further
multi-wavelength observations are critical to characterize the
explosion properties and its host environment. Tentative optical and
radio counterparts were reported in the literature. However, their
positions differ significantly and might be contaminated by other,
unrelated sources. Chandra observations are critical to improve the
positional accuracy of the X-ray transient, to precisely determine its
position with respect to the underlying host galaxy, and to determine
its association with the putative counterparts.
Title : The X-rays of a bright QSO well within the epoch of reionization at
z=7.54
PI: Banados
Abstract: After almost a decade of intense search, our team has finally
discovered a bright QSO well within the epoch of reionization, at
z=7.54. This is by far the most distant QSO known (previous record:
7.08), at a cosmic age of 690 Myr, i.e., only 5% of our universe's
current age. This is the first QSO whose spectrum shows clear evidence
of an intergalactic medium that is >20% neutral and that reionization
is underway. We propose Chandra observations of this unique object to
(i) probe evolution of the X-ray-to-optical luminosity ratio
(alpha-ox) to the highest accessible redshift; (ii) provide a more
reliable estimate of the QSO's bolometric luminosity, and (iii) assess
the feasibility of deeper Chandra and XMM observations for the
upcoming cycles, which would allow us to test whether the first black
holes are accreting at super-Eddington rates.
Title : X-ray confirmation of two intermediate mass black hole candidates
PI: Chilingarian
Abstract: For the last two decades, the international research community has
been hunting the elusive population of intermediate mass black holes
(IMBHs) crucially important for the understanding of galaxy and BH
co-evolution. Despite several good candidates have been found with
various techniques, it is still unclear whether IMBHs existed in the
early Universe and if there is a common way for them to remain intact
as a population till our epoch. We have performed a comprehensive IMBH
search in nearby galaxy nuclei using their optical spectral signatures
(broad Halpha+BPT diagram) combined with advanced data mining in the
Virtual Observatory and identified ~300 candidates with MBH<2e5 Msun,
which pose as low-luminosity active galactic nuclei. The X-ray
detection would confirm their AGN nature and secure the IMBH
classification. We propose to observe 2 IMBH candidates with Chandra
as a pilot project: it will validate our search technique and allow us
to claim the discovery of the IMBH population
Title : X-ray confirmation of two intermediate mass black hole candidates
PI: Chilingarian
Abstract: For the last two decades, the international research community has
been hunting the elusive population of intermediate mass black holes
(IMBHs) crucially important for the understanding of galaxy and BH
co-evolution. Despite several good candidates have been found with
various techniques, it is still unclear whether IMBHs existed in the
early Universe and if there is a common way for them to remain intact
as a population till our epoch. We have performed a comprehensive IMBH
search in nearby galaxy nuclei using their optical spectral signatures
(broad Halpha+BPT diagram) combined with advanced data mining in the
Virtual Observatory and identified ~300 candidates with MBH<2e5 Msun,
which pose as low-luminosity active galactic nuclei. The X-ray
detection would confirm their AGN nature and secure the IMBH
classification. We propose to observe 2 IMBH candidates with Chandra
as a pilot project: it will validate our search technique and allow us
to claim the discovery of the IMBH population
Title : The longest AMXP outburst: looking for pulsation in MAXI J0911-655
after 450 days
PI: Riggio
Abstract: MAXI J0911-655 (J0911) is a new rare accreting millisecond X-ray
pulsar (AMXPs), spinning at ~340 Hz in NGC 2808. Since the latest XMM
observation, the source has been monitored by Swift and INTEGRAL (ATel
#10425). Astonishingly, the source proved to be still in outburst
after more than 450 days. This is by far a record for an AMXP, whose
outburst usually last 2-3 weeks. Standing the current flux of the
source, we propose a 30 ks Chandra HRC-S timing mode DDT ToO aiming to
i) detect the pulsation, ii) obtain a precise spin frequency value to
obtain, for the first time, a direct measurement of the spin frequency
variation (expected to be ~1e-5Hz) during the same outburst, iii)
improve orbital parameters. Those information have strong scientific
return, because the presence of the pulsation will settle the still
debated model of the magnetic field burial under accretion, and the
measurement of nudot will permit to test the accretion mechanism and
the role in it of the magnetic field.
Title : Testing a BeX origin for
PI: Maccarone
Abstract: We would like to extend the exposure time on Chakrabarty's TOO on this
source to 8 ksec. Our goal is to search for pulsations from the
source. It has a position consistent with a blue star with Galactic
reddening and an infrared excess in H band as seen by 2MASS. It also
shows a spectrum with Gamma=0.5+-0.5, which is typical for accreting
high-B field pulsars, but uncommon for low mass X-ray binary
transients. If confirmed, the source would be an X-ray pulsar at 25
kpc, which can be followed up optically. It gives us a start on
understanding the transient populations of the far side of the Galaxy
AND of the outer Galaxy. 8 ksec would allow for a 5 sigma detection of
the pulsation, even in the event of a fading by a factor of a few of
the source, and will give at least 5 cycles for any Be X-ray binary
pulse period.
Title : X-rays as a probe of the progenitor of the Type Ia SN2017cbv
PI: Drout
Abstract: SN2017cbv is a nearby, bright, and young Type Ia SN that was recently
discovered in NGC 5643 (d~15 Mpc) within hours of explosion. Despite
their importance for Cosmology, questions still remain regarding the
nature and diversity of the progenitors that give rise to Type Ia SN.
Progress can be made by obtaining deep X-ray observations---which
probe the density of the CSM shaped by the progenitor system---for SN
which also have tight constraints on their final progenitor
configuration from early (1-2 day) optical/UV light curves. SN2017cbv
represents a rare opportunity when both sets of constraints are
possible. By timing X-ray observations with optical peak, we can probe
densities as low as a few d-9 Msun/yr, enabling us to distinguish
between many giant, main sequence, and double-degenerate progenitors.
SN2017cbv would represent only the third Type Ia SN for which such
deep limits are possible and this study may lead to the first
detection of X-ray radiation from a Type Ia SN.
Title : Puzzling clump with 'whiskers' ejected from a binary
PI: Pavlov
Abstract: Three ACIS-I observations of 2011-2014 allowed us to discover an
extended object moving southwest from the famous high-mass gamma-ray
binary PSR B1259-63/LS 2883 with a surprisingly high velocity, ~0.06c,
perhaps even with acceleration. Such a phenomenon had never been
observed previously. We interpreted it as a clump of stellar matter
ejected from the disk around the massive star near binary periastron
and accelerated and illuminated by the unshocked pulsar wind. The
clump disappeared by 2015 Apr, but a new one was seen emerging from
the binary in 2016 Jan. The latest observation of 2017 Jan 6 showed
the new clump had moved southwest, but its morphology was very
unusual. Most notably, the elongated clump was crossed by narrow
"whiskers" perpendicular to the direction of motion. In addition, a
new extended feature was seen emerging northward from the binary. To
study the evolution of these unexpected features, we request a DDT
observation in April 2017.
Title : M87 with Chandra and the Event Horizon Telescope
PI: Neilsen
Abstract: X-ray observations of accreting black holes are ideal for probing the
physical plasma processes close to the event horizon, which can
include both jet formation and magnetic reconnection leading to flares
and variability. Our ability to study these processes is about to take
a major step forward with the Event Horizon Telescope. During the
period April 5-April 14, the EHT will be online with ALMA and 7 other
stations around the world, and its observations of Sgr A* and M87 may
be the first set of observations capable of resolving the shadow of
these important supermassive black holes. But the ability to interpret
EHT data relies on a proper understanding of the plasma processes and
accretion structure around the black hole, as provided by Chandra. We
have arranged coordinated Sgr A* time; here we are requesting Chandra
time on M87 to probe variability and spectra of the accretion flow and
the jet knot HST-1.
Title : M87 with Chandra and the Event Horizon Telescope
PI: Neilsen
Abstract: X-ray observations of accreting black holes are ideal for probing the
physical plasma processes close to the event horizon, which can
include both jet formation and magnetic reconnection leading to flares
and variability. Our ability to study these processes is about to take
a major step forward with the Event Horizon Telescope. During the
period April 5-April 14, the EHT will be online with ALMA and 7 other
stations around the world, and its observations of Sgr A* and M87 may
be the first set of observations capable of resolving the shadow of
these important supermassive black holes. But the ability to interpret
EHT data relies on a proper understanding of the plasma processes and
accretion structure around the black hole, as provided by Chandra. We
have arranged coordinated Sgr A* time; here we are requesting Chandra
time on M87 to probe variability and spectra of the accretion flow and
the jet knot HST-1.
Title : X-ray flux of the Narrow-Line Seyfert 1 galaxy WPVS 007 during a high
UV flux state
PI: Grupe
Abstract: We request a short, 10ks, observation with Chandra ACIS-S of the
highly X-ray variable Narrow Line Seyfert 1 Galaxy WPVS 007
quasi-simultaneously with HST between March 13 and 26. WPVS 007 is one
of the most unusual AGN showing strong variabilty in broad absorption
lines - a feature that is only seen in high-luminous quasars. We have
monitored WPVS 007 since October 2005 with Swift, but we can typically
not detect it in X-rays. Our last observation of WPVS 007 by Chandra
in March 2015 when it was fount to be in an extremely low UV flux
state (Leighgly et al. 2015) found it at a level of 8e-4 counts/s in
ACIS-s corresponding to a flux in the 0.3-10 keV band of 1e-17 W/m2.
Merging all Swift observaton since then (66ks) results in an 3sigma ul
of 1.4e-17 W/m2. Obtaining a Chandra observation close to the HST
observation will provide us with a crucial flux measurement that will
allow us to determine the intrinsic luminosity of the AGN. Note,
WPVS007 is currently at a bright UV state.
Title : A Hig-Resolution Spectrum of the Black Hole GRS 1716-249
PI: Miller
Abstract: This black hole has been in outburst for several weeks, but it has
only recently become visible with the Swift/XRT and Chandra. The
strong outburst (0.2-0.3 Crab) has been visible with the BAT. On
January 27, we requested a Swift DDT of the source, and the resulting
spectrum is strongly encouraging. The source shows a strong, broad
iron line in just a 1 ks exposure, potentially with wind absorption
lines imprinted as well. We are currently attempting to expand the
number of black holes with spin measurements, and to better understand
the duty cycles of outflows. The XRT exposure gives a flux of 6 E-9
erg/cm2/s in the 0.7-10 keV band. Experience suggests that a 30 ks
HETG spectrum of a source at this flux level will yield a sensitive
Chandra spectrum. A spectrum has been sent to the Director.
Title : Observing Jupiter's X-ray aurora during Juno apojove
PI: Jackman
Abstract: We don't know what causes Jupiter's auroral X-ray emission. Several
drivers (reconnection, Kelvin Helmholtz) have been suggested but all
require testing of local magnetic field and plasma to uniquely
constrain the source region of particles which cause the emission. The
Juno spacecraft at Jupiter has recently had a trajectory change and
will soon explore a previously unplanned region on the dawn flank near
the statistical position of the magnetopause boundary. We have
agreement to use in situ Juno data to complement X-ray observations.
We propose to observe during 3 apojoves, when Juno is furthest from
Jupiter. Depending on local solar wind conditions Juno will either
sample the solar wind, magnetosheath, or boundary layer inside the
magnetopause. Multiple observations will allow us to test X-ray
generation mechanisms under a range of external conditions. No other
mission of this type is planned in our lifetime and these orbits are
our only chance to sample this magnetospheric region.
Title : Observing Jupiter's X-ray aurora during Juno apojove
PI: Jackman
Abstract: We don't know what causes Jupiter's auroral X-ray emission. Several
drivers (reconnection, Kelvin Helmholtz) have been suggested but all
require testing of local magnetic field and plasma to uniquely
constrain the source region of particles which cause the emission. The
Juno spacecraft at Jupiter has recently had a trajectory change and
will soon explore a previously unplanned region on the dawn flank near
the statistical position of the magnetopause boundary. We have
agreement to use in situ Juno data to complement X-ray observations.
We propose to observe during 3 apojoves, when Juno is furthest from
Jupiter. Depending on local solar wind conditions Juno will either
sample the solar wind, magnetosheath, or boundary layer inside the
magnetopause. Multiple observations will allow us to test X-ray
generation mechanisms under a range of external conditions. No other
mission of this type is planned in our lifetime and these orbits are
our only chance to sample this magnetospheric region.
Title : Observing Jupiter's X-ray aurora during Juno apojove
PI: Jackman
Abstract: We don't know what causes Jupiter's auroral X-ray emission. Several
drivers (reconnection, Kelvin Helmholtz) have been suggested but all
require testing of local magnetic field and plasma to uniquely
constrain the source region of particles which cause the emission. The
Juno spacecraft at Jupiter has recently had a trajectory change and
will soon explore a previously unplanned region on the dawn flank near
the statistical position of the magnetopause boundary. We have
agreement to use in situ Juno data to complement X-ray observations.
We propose to observe during 3 apojoves, when Juno is furthest from
Jupiter. Depending on local solar wind conditions Juno will either
sample the solar wind, magnetosheath, or boundary layer inside the
magnetopause. Multiple observations will allow us to test X-ray
generation mechanisms under a range of external conditions. No other
mission of this type is planned in our lifetime and these orbits are
our only chance to sample this magnetospheric region.
Title : iPTF17cw: A relativistic broad-lined type Ic supernova discovered by
iPTF
PI: Corsi
Abstract: Broad-lined supernovae of type Ic (BL-Ic SNe) are a rare form of
massive star core collapse. The link between BL-Ic SNe and gamma-ray
bursts (GRBs) was first made for GRB980425/SN1998bw, which showed
strong radio emission indicative of relativistic expansion. With SN
2009bb, we have learned that some BL-Ic SNe have relativistic ejecta,
but no associated gamma-rays. These "engine-driven" explosions are
extremely rare (one per 5-10 years), and represent the missing link
between ordinary (non-relativistic) BL-Ic SNe and GRBs. iPTF17cw is a
BL-Ic SN discovered by iPTF on 07 Jan 2017, while following-up LIGO
trigger G268556. Regardless of its association with the LIGO trigger,
our VLA radio observations show that this is a rare relativistic
(v~0.8c) BL-Ic SN. We ask for X-ray observations to constrain: (i)
emission mechanism (IC vs synchrotron) and (ii) synchrotron cooling
freq. (which, combined with radio observations, can constrain magnetic
field and ambient density).
Title : Testing a new method for the identification of dual AGN
PI: Secrest
Abstract: Since most galaxies contain massive black holes, and mergers trigger
nuclear accretion, the hierarchical model of galaxy formation predicts
the existence of binary active galactic nuclei (AGN). Confirmed cases
of dual AGN are rare, with efforts for systematic identification
delivering a low yield of confirmed binaries. However, recent
observational and theoretical work has given a new clue in the hunt
for dual AGN: they may preferentially occur in galaxies with very red
mid-IR colors. We have cross-matched the WISE catalog with the 1300
galaxies in the SDSS MaNGA data release. We find a single galaxy with
sufficiently red WISE color (W1-W2=0.84) to classify it as an AGN. Not
only is the host galaxy clearly a spectacular late stage merger, but
the MaNGA IFU data show that the 2 stellar nuclei (separated by ~7
kpc) have optical emission lines consistent with AGN. However, X-ray
observations are required to confirm 2 separate AGN, rather than
extended radiation from a single source.
Title : First Deep X-ray Observations of a Rapid, Luminous and Blue Stellar
Explosion
PI: MARGUTTI
Abstract: We propose the first deep X-ray observations of a rapidly-evolving,
luminous, blue stellar explosion. The new class of rapidly-evolving
luminous transients shows luminosities and time scales of evolution
that challenge the traditional Supernovae (SNe) models. Alternative
scenarios include a failed SN of a stripped star, the detonation of a
helium shell on a white dwarf and a SN shock breaking out from a dense
circumstellar medium. To date, due to their large distances (d>500
Mpc), rapidly evolving luminous transients have only been studied in
the optical/UV regime, which is of thermal origin and it is not
sensitive to the nature of the underlying energy source and properties
of the explosion's fastest ejecta. Here we propose to capitalize on
the unique opportunity to study a recently-discovered, nearby (d=150
Mpc), fast-evolving, luminous transient with Chandra to constrain the
environment and explosion properties of this new class of stellar
explosions for the first time.
Title : First Deep X-ray Observations of a Rapid, Luminous and Blue Stellar
Explosion
PI: MARGUTTI
Abstract: We propose the first deep X-ray observations of a rapidly-evolving,
luminous, blue stellar explosion. The new class of rapidly-evolving
luminous transients shows luminosities and time scales of evolution
that challenge the traditional Supernovae (SNe) models. Alternative
scenarios include a failed SN of a stripped star, the detonation of a
helium shell on a white dwarf and a SN shock breaking out from a dense
circumstellar medium. To date, due to their large distances (d>500
Mpc), rapidly evolving luminous transients have only been studied in
the optical/UV regime, which is of thermal origin and it is not
sensitive to the nature of the underlying energy source and properties
of the explosion's fastest ejecta. Here we propose to capitalize on
the unique opportunity to study a recently-discovered, nearby (d=150
Mpc), fast-evolving, luminous transient with Chandra to constrain the
environment and explosion properties of this new class of stellar
explosions for the first time.
Title : First Deep X-ray Observations of a Rapid, Luminous and Blue Stellar
Explosion
PI: MARGUTTI
Abstract: We propose the first deep X-ray observations of a rapidly-evolving,
luminous, blue stellar explosion. The new class of rapidly-evolving
luminous transients shows luminosities and time scales of evolution
that challenge the traditional Supernovae (SNe) models. Alternative
scenarios include a failed SN of a stripped star, the detonation of a
helium shell on a white dwarf and a SN shock breaking out from a dense
circumstellar medium. To date, due to their large distances (d>500
Mpc), rapidly evolving luminous transients have only been studied in
the optical/UV regime, which is of thermal origin and it is not
sensitive to the nature of the underlying energy source and properties
of the explosion's fastest ejecta. Here we propose to capitalize on
the unique opportunity to study a recently-discovered, nearby (d=150
Mpc), fast-evolving, luminous transient with Chandra to constrain the
environment and explosion properties of this new class of stellar
explosions for the first time.
Title : An X-ray spectrum of a transient supersoft source in the Small
Magellanic Cloud
PI: Maccarone
Abstract: This is a transient supersoft source shown in ATel 9866, where we
found an unabsorbed flux of about 2e-11 in the SMC, with a temperature
of about 80 eV. This object was not in ROSAT, and was also observed by
Swift in response to an optical transient from ASSASN (ATel 9859). The
optical light curves clearly show no nova took place, but we now see a
new supersoft source. It is the first strong case for a supersoft
transient which is not a post-nova. How steady burning starts without
a nova is a mystery, but it may also be a key to understanding the
supersoft sources which are one of the proposed Type Ia supernova
channels. Understanding whether the system has emission lines, pure
continuum, or absorption lines, and which lines it has will determine
whether it really is a supersoft source. Exposure is based on trying
to detect the NVII absorption line at 24.78 Ang expected for a hot WD
(Rauch+ 2010). Tommy Nelson simulated and found a clear detection
requires 50 ksec.
Title : Probing disk wind and other properties of 4U 1630-47
PI: Bhattacharyya
Abstract: The accreting Galactic black hole transient 4U 1630-47, which is
currently in outburst, is an ideal source to probe two types of
accreted matter ejection: (1) via disk wind and (2) via jet, both
using the observed narrow spectral lines (Diaz Trigo et al., 2013,
Nature, 504, 206; Neilsen et al. 2014; Diaz Trigo et al. 2014).
Chandra gratings are ideal to study such lines. The source also showed
indications of high-frequency (HF) quasi-periodic oscillations (QPOs)
in a rather high (150-450 Hz) frequency range, which can be extremely
useful to probe the strong gravity regime. The AstroSat satellite,
because of its large area and high timing resolution in a broad energy
band, can potentially detect and measure HF QPOs and probe the source
broadband spectrum and state. Hence, our proposed 30 ks Chandra
exposure, nearly contemporaneous with complementary AstroSat
observations, will provide an excellent way to probe the accretion and
ejection mechanism in the strong gravity regime.
Title : Constraining the mass of an IMBH candidate in NGC 3310
PI: Earnshaw
Abstract: While much sought-after, intermediate-mass black holes (IMBHs) have so
far remained elusive. Ultraluminous X-ray sources (ULXs) are a good
place to look for IMBHs, and if one appears in the low/hard state we
would expect it to exhibit steady radio jets. A simultaneous
X-ray/radio observation of such an object would allow use of the
fundamental plane (e.g. Merloni et al., 2003) to measure its mass and
confirm its IMBH status. This method has been successfully used before
to identify NGC 2276-3c as a 5e4 solar mass IMBH in Mezcua et al.
(2015). We have found a radio source in NGC 3310 which coincides with
3 ULXs resolved by Chandra, none of which can be identified as the
X-ray counterpart using current radio data. We have been awarded
EVN/e-MERLIN time to attempt to detect and resolve the radio core,
therefore we request quasi-simultaneous observations of this source to
match the radio source with an X-ray source and provide the X-ray
luminosity from which we can calculate the BH mass.
Title : Proxima Cen's Stellar Cycle
PI: Wargelin
Abstract: Based on 15 years of optical monitoring, 4 years of Swift X-ray/UV
data, and 2 HRC observations we find evidence for a 7-yr stellar cycle
in Proxima Cen (dMe5.5), a fully convective star. A stellar cycle is
very exciting because most models of stellar magnetic activity predict
such stars cannot support solar-like cycles. Understanding the
structure and evolution of Proxima's magnetic field is also important
because that's what drives X-ray/UV emission and the stellar wind,
which are important factors in modeling the atmosphere (atmospheric
stripping) and habitability of its newly discovered exoplanet. And as
noted by the discovery announcement, "The robust detection of Proxima
b has only been possible after reaching a detailed understanding of
how the star changes on timescales from minutes to a decade." Further
X-ray measurements are required now, while the cycle appears to be at
a maximum, for confirmaton and to better characterize Proxima's
activity over time.
Title : Proxima Cen's Stellar Cycle
PI: Wargelin
Abstract: Based on 15 years of optical monitoring, 4 years of Swift X-ray/UV
data, and 2 HRC observations we find evidence for a 7-yr stellar cycle
in Proxima Cen (dMe5.5), a fully convective star. A stellar cycle is
very exciting because most models of stellar magnetic activity predict
such stars cannot support solar-like cycles. Understanding the
structure and evolution of Proxima's magnetic field is also important
because that's what drives X-ray/UV emission and the stellar wind,
which are important factors in modeling the atmosphere (atmospheric
stripping) and habitability of its newly discovered exoplanet. And as
noted by the discovery announcement, "The robust detection of Proxima
b has only been possible after reaching a detailed understanding of
how the star changes on timescales from minutes to a decade." Further
X-ray measurements are required now, while the cycle appears to be at
a maximum, for confirmaton and to better characterize Proxima's
activity over time.
Title : Proxima Cen's Stellar Cycle
PI: Wargelin
Abstract: Based on 15 years of optical monitoring, 4 years of Swift X-ray/UV
data, and 2 HRC observations we find evidence for a 7-yr stellar cycle
in Proxima Cen (dMe5.5), a fully convective star. A stellar cycle is
very exciting because most models of stellar magnetic activity predict
such stars cannot support solar-like cycles. Understanding the
structure and evolution of Proxima's magnetic field is also important
because that's what drives X-ray/UV emission and the stellar wind,
which are important factors in modeling the atmosphere (atmospheric
stripping) and habitability of its newly discovered exoplanet. And as
noted by the discovery announcement, "The robust detection of Proxima
b has only been possible after reaching a detailed understanding of
how the star changes on timescales from minutes to a decade." Further
X-ray measurements are required now, while the cycle appears to be at
a maximum, for confirmaton and to better characterize Proxima's
activity over time.
Title : Proxima Cen's Stellar Cycle
PI: Wargelin
Abstract: Based on 15 years of optical monitoring, 4 years of Swift X-ray/UV
data, and 2 HRC observations we find evidence for a 7-yr stellar cycle
in Proxima Cen (dMe5.5), a fully convective star. A stellar cycle is
very exciting because most models of stellar magnetic activity predict
such stars cannot support solar-like cycles. Understanding the
structure and evolution of Proxima's magnetic field is also important
because that's what drives X-ray/UV emission and the stellar wind,
which are important factors in modeling the atmosphere (atmospheric
stripping) and habitability of its newly discovered exoplanet. And as
noted by the discovery announcement, "The robust detection of Proxima
b has only been possible after reaching a detailed understanding of
how the star changes on timescales from minutes to a decade." Further
X-ray measurements are required now, while the cycle appears to be at
a maximum, for confirmaton and to better characterize Proxima's
activity over time.
Title : Chandra Spectroscopy of SMC X-3 in Outburst
PI: Coe
Abstract: SMC X-3 is an HMXB and pulsar in the SMC. It is currently in the midst
of an apparently super-Eddington outburst (10^39 erg/s, or about 10x
Eddington for a neutron star). This is the brightest outburst from
50-60 sources traced by Coe et al. over a decade, and a special
opportunity. The predicted HETGS count rates will give sensitive
spectra. Lines from the massive companion wind are anticipated; if the
source is truly super-Eddington very strong outflows should also be
detected since radiation and gas will be strongly coupled. Simulated
40 ks spectra based on recent XRT observations, including plasma
components, predict 3-5 sigma line detections in the HETGS band.
Stronger detections are expected if a super-Eddington outflow is
present. Recent work on ULXs shows that at least one such source is a
super-Eddington neutron star. SMC X-3 is much closer and may offer
insights into the accretion flow geometry and physical processes in
this rare accretion phase.
Title : Chandra Spectroscopy of SMC X-3 in Outburst
PI: Coe
Abstract: SMC X-3 is an HMXB and pulsar in the SMC. It is currently in the midst
of an apparently super-Eddington outburst (10^39 erg/s, or about 10x
Eddington for a neutron star). This is the brightest outburst from
50-60 sources traced by Coe et al. over a decade, and a special
opportunity. The predicted HETGS count rates will give sensitive
spectra. Lines from the massive companion wind are anticipated; if the
source is truly super-Eddington very strong outflows should also be
detected since radiation and gas will be strongly coupled. Simulated
40 ks spectra based on recent XRT observations, including plasma
components, predict 3-5 sigma line detections in the HETGS band.
Stronger detections are expected if a super-Eddington outflow is
present. Recent work on ULXs shows that at least one such source is a
super-Eddington neutron star. SMC X-3 is much closer and may offer
insights into the accretion flow geometry and physical processes in
this rare accretion phase.
Title : Revealing the nature of the mysterious new SMC Transient: Swift
J003233.6-7306
PI: Kennea
Abstract: Starting June 8th, 2016, the Swift SMC Survey, AKA S-CUBED (Kennea et
al., ATEL #9299), began a weekly shallow X-ray survey of the SMC to
search for >1% L_Edd X-ray transients. We have discovered a new
puzzling X-ray transient Swift J003233.6-7306, on the western edge of
the SMC. A NuSTAR DDT observation revealed a hard X-ray spectrum
(Gamma = 1.7), canonical for a BH LMXB in the low/hard state, or
possibly Be/X-ray binary (common in the SMC). The Swift position is
not consistent with any optical counterpart, which is puzzling if a
binary, however given the error in the position from Swift (~4") we
cannot rule out nearby stars as the counterpart. We request a short
(1ks) Chandra in order to localize this transient to the at least ~1"
accuracy needed to definitively identify any counterpart in deep
optical data obtained on the field by OGLE. A firm detection or
non-detection in optical, given the low absorption towards the source,
would place strong constraints on the object type.
Title : Prompt Chandra observations of PSR J1119-6127 and its compact nebula
following its magnetar-like burst
PI: Blumer
Abstract: PSR J1119-6127 is a high-magnetic (B) field pulsar with spin
properties (P=408 ms, age=1.7 kyr, B=4.1e13 G) similar to those of
J1846-0258, the first high-B pulsar to show magnetar-like behavior and
one of a handful for which a braking index has been measured
(n=2.91+/-0.05). Chandra studies of J1119-6127 allowed the first
detection of the X-ray counterpart and revealed the evidence for a
compact and faint pulsar wind nebula (PWN; Gonzalez & Safi-Harb 2003
ApJ, 591, 143). A follow up study found evidence for an elongated jet
to the south, and resolved the PSR spectrum from its compact PWN
spectrum for the first time (Safi-Harb & Kumar, 2008, ApJ, 684, 532).
J1119-6127 is considered as a key source in our understanding of the
physical characteristics and processes that differentiate radio
pulsars from magnetars. Just like J1846-0258 , it was predicted that
J1119-6127 will one day reveal itself as a magnetar after an
occasional burst driven by its high B-field.
Title : Down with the King: FO Aqr in an Extended Low State
PI: Kennedy
Abstract: FO Aquarii, the so called king of the intermediate polars, is in an
unprecedented and prolonged faint state. Normally brighter than V =
14, FO Aqr is currently at V ~15 and was as faint as V~15.7 at the
start of 2016 May. The faint state began at unknown time between 2015
Dec. 18 (V = 13.71, S. Dvorak, AAVSO) and 2016 May 6 (V ~ 15.6, our
measurement). (For more, including the long term light curve, see
http://www.astronomerstelegram.org/?read=9216) Recent optical
observations have also shown the pulsations to now have a period of
around 11.1 mins (http://www3.nd.edu/~clittlef/FOaqr.png), suggesting
the 2 accretion poles are currently visible. This may be due to a
change in the accretion geometry. We wish to investigate changes to
the x-ray flux and spectrum, and whether the x-ray spin period, which
was seen to be 20.9 mins by Evans et al. (2004, MNRAS, 349, 715) using
XMM-Newton, has also changed to the 10 mins seen in the new optical
data.
Title : Measuring the spin period of XMMU J004855.5-734946 during a large
outburst
PI: Vasilopoulos
Abstract: Spin periods of Be/X-ray binary (BeXRB) pulsars are important for
probing their formation channels and the connection between orbital
period and pulsar spin in XRBs (Knigge+ 2011). From the 120 BeXRBs in
the SMC only 50% have known spin periods, with the majority of them
measured during outburst with ToOs. From the remaining systems only 6
have a known orbital period. XMMU J004855.5-734946 is a BeXRB in the
SMC (Haberl & Sturm 2016, XMM Lx ~(0.03-1)x10^35 erg/s) with a 36.43d
orbital period (Atel#9198), but with no X-ray pulsations detected so
far. On 06/24 a 37s Swift/XRT observation detected the system at
Lx~10^37 erg/s (Atel#9197) following a marginal detection on 06/16
(Lx<5x10^36 erg/s) confirming the onset of a large outburst. A
follow-up 1ks Swift ToO on 06/29 measures an Lx = 8.3x10^36 erg/s.
This is a unique opportunity to measure the spin period of one of the
few BeXRBs in the SMC with known orbital period but unknown spin
period.
Title : SGR 1935+2154 in a very active state
PI: Kouveliotou
Abstract: The magnetar SGR 1935+2154 has been active since the middle of May
2016 emitting several bursts per day that have triggered the
Fermi/GBM. The burst intensities have been gradually increasing and on
June 26, 2016 the source emitted a very bright burst indicating
potential extreme further source activity. The source persistent
emission properties are strongly influenced by such activity, both in
timing and spectra. We request a Chandra DDT observation to study the
change of the persistent source properties, and potentially study
similar properties for serendipitously recorded bursts. In particular,
we note that the currently reported Nh (GCN 15590) its 3 times higher
than the one measured in the past (Israel etal. 2016) which leads us
to believe that the recent burst is accompanied with metal enhanced
outflow.
Title : Chandra Observations of the Brightest and Closest H-poor Superluminous
Supernova Gaia16apd
PI: Yan
Abstract: Gaia16apd was first triggered as a 17.3 mag transient (now 16.5mag) on
2016-05-16 by GAIA. The first optical spectrum on 2016-05-20.92 UT
classified it as a H-poor superluminous supernova (SLSN-I) at z=0.102
and absolute magnitude of -21.0 (Atel #9071). This makes Gaia16apd one
of the brightest and the closest SLSNe-I. SWIFT observations on
2016-05-21 revealed an extremely UV bright source, 15.3mag at 2310A.
Gaia16apd has similar apparent brightness as ASASN-15lh, the most
luminous SLSN-I ever discovered. ASASN-15lh has been observed by
Chandra, and was reported with detections. Magnetar models (Metzger et
al. 2014,Fig.12) predicted that SLSNe-I should have X-ray emission
post optical-peak. With the predicted fluxes well within the Chandra
limit in 10ksec, Gaia16apd offers the unique opportunity to constrain
theoretical models. The proposed observation will shed light on the
long standing mystery of what powers the luminous optical emission
from SLSN-I.
Title : Chandra Observations of the Brightest and Closest H-poor Superluminous
Supernova Gaia16apd
PI: Yan
Abstract: Gaia16apd was first triggered as a 17.3 mag transient (now 16.5mag) on
2016-05-16 by GAIA. The first optical spectrum on 2016-05-20.92 UT
classified it as a H-poor superluminous supernova (SLSN-I) at z=0.102
and absolute magnitude of -21.0 (Atel #9071). This makes Gaia16apd one
of the brightest and the closest SLSNe-I. SWIFT observations on
2016-05-21 revealed an extremely UV bright source, 15.3mag at 2310A.
Gaia16apd has similar apparent brightness as ASASN-15lh, the most
luminous SLSN-I ever discovered. ASASN-15lh has been observed by
Chandra, and was reported with detections. Magnetar models (Metzger et
al. 2014,Fig.12) predicted that SLSNe-I should have X-ray emission
post optical-peak. With the predicted fluxes well within the Chandra
limit in 10ksec, Gaia16apd offers the unique opportunity to constrain
theoretical models. The proposed observation will shed light on the
long standing mystery of what powers the luminous optical emission
from SLSN-I.
Title : An outburst of the CCO 1E161348-5055: an accreting neutron star or a
peculiar binary magnetar?
PI: Rea
Abstract: The INS 1E161348-5055 is a Central Compact Object (CCOs) in the center
of the 2kr young SNR RCW103. It has been an intriguing source all
along. Several hypothesis about the nature of 1E1613 have been
proposed as a binary neutron star system, a very slow magnetar or even
a CV (see Pizzolato et al. 2008). The bright thermal X-ray emission of
other CCOs, and the low dipolar B field (~10^11 G), have been
interpreted as evidence of "hidden" strong magnetic fields within the
CCO crusts, burried by accretion. 1E1613 was instead considered an
outlier because of the lack of pulsation, but the presence of a
peculiar 6.4hr periodicity. Our undergoing Swift monitoring of 1E16134
show the source at a flux of a factor of 10 higher, and with a harder
spectrum (PL ~1.7) than usual (see figure in the link). Furthermore,
apparently Swift BAT detected a "possible"burst from this direction
(GCN 19547/GRB 160622A), although its association with the CCO is
still unclear (if any).
Title : Understanding the Mass-Loss History of the Progenitors of Type IIn
Supernovae: SN 2016bkv
PI: Patnaude
Abstract: The mass-loss history of massive stars is one of the least understood
and yet fundamental aspects of stellar evolution. HOW and WHEN do
massive stars shed their massive envelopes? Is there a relationship
between the expulsion of the stellar envelope and core-collapse? These
central, yet open questions motivate the present investigation. In
regards to these questions, studying the evolution of a supernova
shock as it interacts with the ejected envelope of the progenitor
provides insight into how much mass was lost and perhaps most
importantly, when it was lost relative to core-collapse. X-ray
emission from the shocked gas probes the dynamics of the interaction
and, when combined with other ongoing and planned multi-wavelength
observations, serves to constrain properties of the surrounding
circumstellar gas and the end-stages of the progenitor's evolution. We
propose to study SN2016bkv in order to understand the final mass-loss
phase prior to the core-collapse of its progenitor.
Title : An exceptionally cold neutron star in HETE J1900.1-2455
Title : Detecting an X-ray Counterpart to an Active TeV Flaring Event in the
Title : Detecting an X-ray Counterpart to an Active TeV Flaring Event in the
Title : Detecting an X-ray Counterpart to an Active TeV Flaring Event in the
Title : Detecting an X-ray Counterpart to an Active TeV Flaring Event in the
Title : Detecting an X-ray Counterpart to an Active TeV Flaring Event in the
Title : Image D Of Huchra's Lensed Quasar: Waiting For The Other Shoe To Drop
Title : SN2005ip awakens: an unprecedented glimpse of explosive mass-loss
Title : The accretion disk of a rare jet-driving symbiotic binary during its
Title : The accretion disk of a rare jet-driving symbiotic binary during its
Title : Catching a Changing Look Quasar as it retreats to the Shadows for the
Title : Confirming X-ray brightening of the PSR J2032+4127 binary system
Title : The Young Type IIP Supernova ASASSN-16at
Title : X-ray irradiation and evaporation of a likely ocean planet
Title : X-ray irradiation and evaporation of a likely ocean planet
Title : Search for an X-ray counterpart from a repeating Fast Radio Burst
Title : High Spatial/Temporal Resolution Chandra Follow-up of the 2015
Title : Simultaneous Chandra and NuSTAR Observations of the Highly Obscured
Title : Chandra Observations of Pluto's Escaping Atmosphere in Support of the
Title : Chandra Observations of Pluto's Escaping Atmosphere in Support of the
Title : Light Echoes from V404 Cyg
Title : Chandra Observations of Pluto's Escaping Atmosphere in Support of the
Title : The Next Step for V404 Cyg
Title : Detecing Super-Eddington Driven Winds in V404 Cyg
Title : Detecing Super-Eddington Driven Winds in V404 Cyg
Title : The brightening of M82: The intermediate mass black hole or ultra
Title : Mapping the evolution of SNhunt275 to shed light onto the last
Title : Mapping the evolution of SNhunt275 to shed light onto the last
Title : Snapshot observations of 2S1553-542: determination of the source
Title : The Structure of the Accretion Flow in SAX J1808.4-3658 at Low
Title : Search for a Jet Break in the Short GRB 150423A
Title : Seizing a rare opportunity to catch a disk wind in a neutron star
Title : GK Persei in the current dwarf-nova-like outburst
Title : The dim state of RW Aur
Title : Calibration of the ACIS GRADED mode using the Cas A CCO
Title : Chandra Observation of 'GRB 150301C' / [PFH2005] 622
Title : X-ray Flux of the Narrow Line Seyfert 1 Galaxy WPVS 007 during an
Title : X-ray follow-up of a fast radio burst
Title : Simultaneous UV and X-ray spectroscopy with HST and Chandra: observing
Title : A second look for variability in the exceptional Swift J123205.1-1056
Title : Understanding the nature of the peculiar transient Swift
Title : The unprecedented metamorphosis of SN2014C
Title : The unprecedented metamorphosis of SN2014C
Title : The unprecedented metamorphosis of SN2014C
Title : A High-resolution Spectrum of an Unprecedented Tidal Disruption Event
Title : A High-resolution Spectrum of an Unprecedented Tidal Disruption Event
Title : A second HLX-1-like object in CXO J122518.6+144545
Title : A second HLX-1-like object in CXO J122518.6+144545
Title : Deep Chandra observations to put the deepest limits to the density of
Title : An unusual brightening of a non-active galaxy nucleus
Title : A candidate 30,000 solar mass black hole
Title : Measuring the period derivative of the newly discovered magnetar SGR
Title : The new outburst of the EXor V1180 Cas as observed at X and NIR
Title : Chandra/H.E.S.S. follow-up of PSR B1259-63 gamma-ray flare
Title : Chandra/H.E.S.S. follow-up of PSR B1259-63 gamma-ray flare
Title : Late-time X-rays to constrain the true energy, jet geometry and burst
Title : A Harder Look at the Bursting Pulsar
Title : A Harder Look at the Bursting Pulsar
Title : A rare opportunity to resolve the emission line complex in GRO
Title : The dynamical X-ray nebula powered by the high-mass binary PSR
Title : X-rays to probe the environment and the progenitor of Type Ia SN2014J
Title : X-ray driven evaporation of exoplanet atmospheres: discovery of a
Title : The dynamical X-ray nebula powered by the high-mass binary PSR
Title : Catching the rebirth of a radio millisecond pulsar
Title : Constraining the progenitor mass-loss and shock parameters around a
Title : A search for absorption features in the afterglow of the unusual GRB
Title : GRB130831A: the birth of a magnetar
Title : GRB130831A: the birth of a magnetar
Title : The Energetics of the High-Redshift GRB 130606A
Title : A direct constraint on the mass of an IMBH candidate in NGC 2276
Title : The unusual state of Mrk 590
Title : An intermediate-mass black hole candidate in NGC 404
Title : Chandra observation of the newly discovered transient IGR J18245-2452
Title : High Latitude Charge Exchange X-rays from Comet PANSTARRS in the Cold
Title : High Latitude Charge Exchange X-rays from Comet PANSTARRS in the Cold
Title : High Latitude Charge Exchange X-rays from Comet PANSTARRS in the Cold
Title : Confirm the Nuclear Origin of the Post-flare Hard Spectrum from a
Title : High Latitude Charge Exchange X-rays from Comet PANSTARRS in the Cold
Title : High Latitude Charge Exchange X-rays from Comet PANSTARRS in the Cold
Title : High Latitude Charge Exchange X-rays from Comet PANSTARRS in the Cold
Title : High Latitude Charge Exchange X-rays from Comet PANSTARRS in the Cold
Title : High Latitude Charge Exchange X-rays from Comet PANSTARRS in the Cold
Title : Localizing NuSTAR J163433-473838: the First Source Discovered by
Title : Understanding the X-ray temperature vs life time dependence of novae
Title : Investigating the nature of the transient source in M 82
Title : Observation of a possible 'orphan' GRB afterglow
Title : Nova Mon 2012 as a luminous supersoft X-ray source
Title : Sw1644+57: a relativistic jet that switched on and is now switching
Title : Grating Spectroscopy of early hard X-ray emission in Nova Mon 2012
Title : The outflow geometry of the short GRB 120804A
Title : 1E 2259+586: Detecting Particle Outflow from an Active Magnetar
Title : Disclosing the position of the naked-eye-alike GRB120624B's afterglow
Title : Unveiling an intermediate-mass black hole in the spiral galaxy NGC
Title : An HETGS Observation of Extreme Activity in 4U 1630-47
Title : Swift J1753.5-0127 in the soft state: signatures of an outflowing
Title : Nova LMC 2012 at high spectral resolution
Title : An HETGS Observation of the Transient MAXI J1305-704
Title : Supernova PTF 11qcj: first discovery of a radio luminous Ibn
Title : X-ray followup of type IIP SN 2011ja
Title : X-ray irradiation and evaporation of a super-Earth exoplanet
Title : X-ray irradiation and evaporation of a super-Earth exoplanet
Title : Supernova PTF 11qcj: first discovery of a radio luminous Ibn
Title : Supernova PTF 11qcj: first discovery of a radio luminous Ic SN
Title : Chandra Astrometry of a New ULX in NGC 891
Title : Studying the physics of outbursts in the Westerlund 1 transient
Title : Chandra Observations of the Nearest Type Ia SN in 25 Years
Title : Chandra spectroscopy of the X-ray spectrum of the newly discovered
Title : Chandra spectroscopy of the X-ray spectrum of the newly discovered
Title : Is Swift J1834.9-0846 a magnetar related to SNR W41 and HESS
Title : Resolving the mystery of GRB 110709B
Title : Determination of the true nature of Swift J1822.3-1606
Title : Swift J2058+0516: A Second Prompt Relativistic Outflow from a Massive
Title : Which M15 Source Is Now in Outburst?
Title : Confirmation of a New Pulsar Wind Nebula
Title : Chandra Follow-up of an Exceptional GALEX+PS1 Tidal Disruption Event
Title : Probing the neutron star crust of the new transiently accreting 11 Hz
Title : Hot wind and accretion in TW Hya
Title : Searching for the pulsar powering the new TeV binary HESS J0632+057
Title : Observing the crust cooling in the 11 Hz accreting pulsar in the
Title : Measuring the Spin of the Black Hole Cgynus X-1, Phase 2
Title : Unveiling the nature of cyclic behavior in the period evolution of the
Title : An Unusual Outburst from the Nucleus of the Quiescent Galaxy NGC 1589
Title : Monitoring of the Crab Nebula
Title : Monitoring of the Crab Nebula
Title : Monitoring of the Crab Nebula
Title : Monitoring of the Crab Nebula
Title : Monitoring of the Crab Nebula
Title : Monitoring of the Crab Nebula
Title : Monitoring of the Crab Nebula
Title : The bolometric luminosity of the z=7.08 QSO ULAS J1120+0641
Title : Confirming the low-mass X-ray binaries in the Kepler field
Title : Confirming the low-mass X-ray binaries in the Kepler field
Title : Confirming the low-mass X-ray binaries in the Kepler field
Title : Confirming the low-mass X-ray binaries in the Kepler field
Title : Confirming the low-mass X-ray binaries in the Kepler field
Title : Confirming the low-mass X-ray binaries in the Kepler field
Title : Confirming the low-mass X-ray binaries in the Kepler field
Title : Confirming the low-mass X-ray binaries in the Kepler field
Title : Confirming the low-mass X-ray binaries in the Kepler field
Title : High resolution spectroscopy of the 11 Hz eclipsing pulsar in Terzan
Title : Study of spatial structure associated with a gamma-ray enhancement of
Title : Study of spatial structure associated with a gamma-ray enhancement of
Title : Study of spatial structure associated with a gamma-ray enhancement of
Title : Study of spatial structure associated with a gamma-ray enhancement of
Title : Study of spatial structure associated with a gamma-ray enhancement of
Title : Unveiling the nature of cyclic behavior in the period evolution of the
Title : The first low-B soft gamma repeater: testing the magnetar model
PI: Degenaar
Abstract: The ~1 km thick crust of neutron stars is strongly heated by nuclear
reactions during accretion outbursts, but cools in quiescence. HETE
J1900.1-2455 continously accreted since 2005, but in 2015 late Oct its
intensity dropped below the detection limit of MAXI. Swift
observations (Mar 7) fail to detect the source, implying Lx
highly unexpected, as the crust should have been significantly heated
during the ~9 yr outburst: our studies of 5 other sources after >1 yr
outbursts revealed hot neutron star crusts of >100 eV. This remarkable
result suggests that nuclear heating may not always be efficient, a
scenario that has never been considered to explain exceptionally cold
neutron stars such as SAX J1808.4-3658 and 1H1905+000. With a 30 ks
DDT, we can put firm constraints on the crust temperature in HETE
J1900 (kT~33 eV; Lx~2e30 erg/s), with important implications for
neutron star heating/cooling models.
M87 Jet
PI: Cheung
Abstract: M87 is currently in an active TeV flaring state with 7% Crab detection
March 7 (4.1 sigma; VERITAS), confirmed at 8% Crab on March 8 (3.6
sigma; MAGIC) satisfying threshold for triggering monitoring with all
three TeV telescopes. Previous TeV high-states lasted 1-2 week saw
day-scale flares at >3x the ~2% Crab quiescent flux. TeV flaring was
seen thrice previously since regular monitoring began in 2004. Sparse
1-2 week interval Chandra coverage in 2005 & 2008 gave ambiguous
results. In 2010 the first of 5 daily Chandra ToO exposures was
obtained in just <3 days from our trigger but the TeV flare subsided.
Thus the first Chandra observation in Mar 2016 should commence asap in
order to isolate TeV emission site in M87 via correlated variability
while in high TeV state. M87 nucleus and 0.8" offset jet knot HST-1
are known X-ray variable and Chandra can separate their
contributions.
M87 Jet
PI: Cheung
Abstract: M87 is currently in an active TeV flaring state with 7% Crab detection
March 7 (4.1 sigma; VERITAS), confirmed at 8% Crab on March 8 (3.6
sigma; MAGIC) satisfying threshold for triggering monitoring with all
three TeV telescopes. Previous TeV high-states lasted 1-2 week saw
day-scale flares at >3x the ~2% Crab quiescent flux. TeV flaring was
seen thrice previously since regular monitoring began in 2004. Sparse
1-2 week interval Chandra coverage in 2005 & 2008 gave ambiguous
results. In 2010 the first of 5 daily Chandra ToO exposures was
obtained in just <3 days from our trigger but the TeV flare subsided.
Thus the first Chandra observation in Mar 2016 should commence asap in
order to isolate TeV emission site in M87 via correlated variability
while in high TeV state. M87 nucleus and 0.8" offset jet knot HST-1
are known X-ray variable and Chandra can separate their
contributions.
M87 Jet
PI: Cheung
Abstract: M87 is currently in an active TeV flaring state with 7% Crab detection
March 7 (4.1 sigma; VERITAS), confirmed at 8% Crab on March 8 (3.6
sigma; MAGIC) satisfying threshold for triggering monitoring with all
three TeV telescopes. Previous TeV high-states lasted 1-2 week saw
day-scale flares at >3x the ~2% Crab quiescent flux. TeV flaring was
seen thrice previously since regular monitoring began in 2004. Sparse
1-2 week interval Chandra coverage in 2005 & 2008 gave ambiguous
results. In 2010 the first of 5 daily Chandra ToO exposures was
obtained in just <3 days from our trigger but the TeV flare subsided.
Thus the first Chandra observation in Mar 2016 should commence asap in
order to isolate TeV emission site in M87 via correlated variability
while in high TeV state. M87 nucleus and 0.8" offset jet knot HST-1
are known X-ray variable and Chandra can separate their
contributions.
M87 Jet
PI: Cheung
Abstract: M87 is currently in an active TeV flaring state with 7% Crab detection
March 7 (4.1 sigma; VERITAS), confirmed at 8% Crab on March 8 (3.6
sigma; MAGIC) satisfying threshold for triggering monitoring with all
three TeV telescopes. Previous TeV high-states lasted 1-2 week saw
day-scale flares at >3x the ~2% Crab quiescent flux. TeV flaring was
seen thrice previously since regular monitoring began in 2004. Sparse
1-2 week interval Chandra coverage in 2005 & 2008 gave ambiguous
results. In 2010 the first of 5 daily Chandra ToO exposures was
obtained in just <3 days from our trigger but the TeV flare subsided.
Thus the first Chandra observation in Mar 2016 should commence asap in
order to isolate TeV emission site in M87 via correlated variability
while in high TeV state. M87 nucleus and 0.8" offset jet knot HST-1
are known X-ray variable and Chandra can separate their
contributions.
M87 Jet
PI: Cheung
Abstract: M87 is currently in an active TeV flaring state with 7% Crab detection
March 7 (4.1 sigma; VERITAS), confirmed at 8% Crab on March 8 (3.6
sigma; MAGIC) satisfying threshold for triggering monitoring with all
three TeV telescopes. Previous TeV high-states lasted 1-2 week saw
day-scale flares at >3x the ~2% Crab quiescent flux. TeV flaring was
seen thrice previously since regular monitoring began in 2004. Sparse
1-2 week interval Chandra coverage in 2005 & 2008 gave ambiguous
results. In 2010 the first of 5 daily Chandra ToO exposures was
obtained in just <3 days from our trigger but the TeV flare subsided.
Thus the first Chandra observation in Mar 2016 should commence asap in
order to isolate TeV emission site in M87 via correlated variability
while in high TeV state. M87 nucleus and 0.8" offset jet knot HST-1
are known X-ray variable and Chandra can separate their
contributions.
PI: Pooley
Abstract: In mid-2013, image D of Huchra's Lens began fading precipitously in
the optical (as seen by OGLE). One expects corresponding brightness
changes in X-rays, as the X-ray region is thought to be smaller, by a
factor of 4, than the optical continuum region (Mosquera et al), but
with the changes occurring more rapidly. At the start of the 2014 OGLE
season (MJD 56826), image D was 0.7 mag fainter than in mid-2013. Our
analysis of archival Chandra data shows that there was no X-ray drop
on MJD 56815 compared to Chandra data from mid- to late-2013. This is
somewhat surprising, and it would be even more surprising if image D
were still as bright as on MJD 56815, given the continuing decline in
the optical (during 2015, image D had fallen ~2 mag below its mid-2013
level); this would (uncomfortably) imply that the X-rays and optical
come from separate non-concentric regions. We request a 30 ks
observation of 2237+0305 to determine whether image D has also fallen
by a factor of ~6 in X-rays.
10,000 years before core-collapse
PI: Mauerhan
Abstract: SNe interacting with circumstellar material (CSM) have raised critical
questions about the latest phases of massive-star evolution. SN 2005ip
is a case where >15 MSun of CSM was ejected by the luminous blue
variable (LBV) progenitor several years before core collapse,
reminiscent of Eta Car's historic eruption. So far we have no
explanation for the cause of pre-SN eruptions; potential factors
include late nuclear burning stages, or violent binary encounters.
After a decade of steadily fading interaction with stellar wind,
SN2005ip began interacting strongly this month with a distant dense
structure of CSM ejected 10,000 yr before the SN, providing an
unprecedentedly distant look-back time on the progenitor's pre-SN
mass-loss history. The CSM could have an origin similar to the ring
around SN1987A, also launched 10,000 yr before SN. We request DDT
ACIS-S observations of 2005ip before it fades, to measure the
interaction energy and mass of the CSM, in order to elucidate its
origin.
brightest outburst in a ~century
PI: Lucy
Abstract: The current optical outburst (ATel#8653) of the symbiotic star
(interacting white dwarf [WD] + red giant) MWC 560, its brightest in
>87 years, provides a rare opportunity to examine the physics of jet
production in the otherwise well-understood context of WD accretion.
This proposal's goal is to use X-ray emission from the accretion-disk
boundary layer to characterize changes in the disk associated with
strong jet production/acceleration. MWC 560 drives a jet, and optical
spectra taken over 2 months during the peak of the last outburst, 26
years ago, showed Balmer absorption velocities increasing from 3000
km/s to their record velocity of 6000 km/s (Tomov et al. 1990).
300-2800 km/s Balmer troughs have just been observed, suggesting the
early phase of jet acceleration. Chandra will reveal whether the
jet-driving disk remains intact and brightens in X-rays (we expect the
boundary layer to remain optically thin) or the degree to which the
inner disk is evacuated (as in X-ray binaries).
brightest outburst in a ~century
PI: Lucy
Abstract: The current optical outburst (ATel#8653) of the symbiotic star
(interacting white dwarf [WD] + red giant) MWC 560, its brightest in
>87 years, provides a rare opportunity to examine the physics of jet
production in the otherwise well-understood context of WD accretion.
This proposal's goal is to use X-ray emission from the accretion-disk
boundary layer to characterize changes in the disk associated with
strong jet production/acceleration. MWC 560 drives a jet, and optical
spectra taken over 2 months during the peak of the last outburst, 26
years ago, showed Balmer absorption velocities increasing from 3000
km/s to their record velocity of 6000 km/s (Tomov et al. 1990).
300-2800 km/s Balmer troughs have just been observed, suggesting the
early phase of jet acceleration. Chandra will reveal whether the
jet-driving disk remains intact and brightens in X-rays (we expect the
boundary layer to remain optically thin) or the degree to which the
inner disk is evacuated (as in X-ray binaries).
Second Time
PI: Tremblay
Abstract: We propose an urgent, exciting, and short (30 ksec) Chandra DDT
observation of Mrk 1018, enabling a first-ever observation of a quasar
returning to an obscured Type 2 (narrow-lined) state *for the second
time*. In 1986, the source was identified as one of the first-known
``changing look" quasars, transitioning from a Seyfert 1.9 to a
Seyfert 1 nucleus. This extreme variability was due either to dramatic
intermittency in the accretion rate, or because an eclipsing cloud
vacated our line of sight, revealing the broad line region. Last week,
in examining our new VLT/MUSE IFU data for this source (obtained as
part of the CARS survey, www.cars-survey.org), we were astonished to
discover that the source has just now reverted *back* to a
narrow-lined Seyfert 1.9. Optical photometry shows that the AGN has
dimmed by an entire magnitude over the past year, and shows no signs
of slowing. Chandra is urgently needed to directly test both
hypotheses (i.e., cloud passage vs. accretion rate change).
PI: Ho
Abstract: We propose a 5 ks observation of the radio and gamma-ray pulsar PSR
J2032+4127 and its binary (Be-star) companion MT91-213. Even though
there are many known Be-neutron star binaries, this system is unique
in many ways, including its very long and eccentric orbit, proximity
(1.4 kpc), and careful radio monitoring and timing. Neutron stars in
these types of binaries usually undergo luminous X-ray outbursts
during periastron, as they accrete matter from their Be-star
companion. PSR J2032+4127 will reach periastron in early 2018, and the
anticipated X-ray outburst (and radio monitoring) will provide
important insights into the accretion process and physics of neutron
stars and their magnetic fields. Our proposed short observation is
needed in order to produce a baseline for the upcoming outburst,
especially with several other nearby X-ray bright sources.
PI: Grupe
Abstract: We propose to observe a young (~5-day old), nearby (16 Mpc) type IIP
supernova ASASSN-16at with Chandra for 5ks. We tentatively detect the
supernova with Swift XRT. Chandra had observed the field in November
2005, but no X-ray source was found, strengthening the possibility
that the Swift detections are associated with the supernova. However,
precise Chandra astrometry is needed to establish the association.
Detections of SNe IIP this early are rare - only 3 have been detected
in X-rays within the first 10 days. Such very early phase X-ray
detection can put important constraint on its immediate circumstellar
exploding environment, which can subsequently probe the mass loss mode
of the RSG progenitor within a decade before the explosion.
Furthermore, the tentative Swift detection places ASASSN-16at among
the most luminous SNe IIP in X-ray, and the Chandra measurement will
test the recently proposed upper limit on the RSG progenitor mass loss
rate for this class of supernovae.
PI: Wheatley
Abstract: The super-Earth transiting the bright K star HD97658 (V=7.7) has a
density impling a bulk composition dominated by water. X-ray/EUV
irradiation of the planet is expected to photodissociate the water
envelope and drive a hydrogen-rich wind that should be detectable at
Lyman-alpha with HST/STIS. We have HST transit observations scheduled
for Dec and Jan that are designed to detect the escaping hydrogen and
establish the presence of a water reservoir on HD97658b. This would be
the first signature of an evaporating ocean on an exoplanet. Here we
request Chandra observations to measure the mean X-ray flux of the
star in the hours preceding the two HST observations. This will allow
us to determine the energetic efficiency of atmospheric escape in the
case of detected absorption, or to place limits on the abundance of
water in the absence of absorption. Chandra coverage of both transits
will allow us to interpret variability in water loss in the context of
the changing radiation environment.
PI: Wheatley
Abstract: The super-Earth transiting the bright K star HD97658 (V=7.7) has a
density impling a bulk composition dominated by water. X-ray/EUV
irradiation of the planet is expected to photodissociate the water
envelope and drive a hydrogen-rich wind that should be detectable at
Lyman-alpha with HST/STIS. We have HST transit observations scheduled
for Dec and Jan that are designed to detect the escaping hydrogen and
establish the presence of a water reservoir on HD97658b. This would be
the first signature of an evaporating ocean on an exoplanet. Here we
request Chandra observations to measure the mean X-ray flux of the
star in the hours preceding the two HST observations. This will allow
us to determine the energetic efficiency of atmospheric escape in the
case of detected absorption, or to place limits on the abundance of
water in the absence of absorption. Chandra coverage of both transits
will allow us to interpret variability in water loss in the context of
the changing radiation environment.
PI: Scholz
Abstract: Fast radio bursts (FRBs) are a new class of ms bursts discovered using
the Parkes radio telescope (Thornton et al. 2013). FRBs appear to be
one-off events with very large dispersion measures (DM) that suggest
cosmological distances, but unknown origins. Last year, we discovered
the first non-Parkes FRB 121102, DM=557 pc cm^-3, 3x the predicted
Galactic column (Spitler et al. 2014). Remarkably, we detected ~10
more bright radio bursts in Arecibo data from June at the same DM. We
have just detected another burst on Nov 13th using GBT. The June
bursts suggest a period of 8s. This period is typical of magnetars.
This thus could be an extra-Galactic magnetar, and may solve the FRB
mystery. This sky position has yet to be observed by any X-ray
telescope other than ROSAT whose response is too soft to be useful. We
request Chandra DDT time to search for an X-ray counterpart which
would test the magnetar hypothesis and, crucially, localize the
source, thus enabling an ID of a galaxy host.
outburst of the X-ray pulsar SMC X-2
PI: Li
Abstract: Accretion and propeller are the major processes driving the pulsar
evolution. SMC X-2, a 2.37s X-ray pulsar (Corbet+ 2000), is one of a
few important examples showing strong accretion outbursts and low
accretion propeller quiescences, occasionally. 2 close (2") possible
optical counterparts, a variable brighter Oe and a stable fainter Be,
have been reported (Schmidtke+ 2006). In 2015 Sep, Swift/BAT and
MAXI/GSC independently detected an outburst at 15 mCrab. A rapid XRT
ToO confirms the result with the best ever accurate localization at
<3.6". But still, depending on how the XRT astrometry is done, both
the reported counterparts can be real. While our analysis on the most
recent XRT data (WT) tentatively shows the spin period is by 0.001s
faster than the one detected by RXTE/ASCA in 2000, a more sensitive
data is required to confirm this. We thus request a 2.8ks timing mode
HRC-S observation to 1) determine the optical companion and 2) verify
spin-up history over the last 15 years.
AGN Candidate in NGC660.
PI: Annuar
Abstract: We are using NuSTAR to undertake a detailed investigation of the
obscured AGN population at D<15Mpc. Our latest target is NGC660 where
the presence of an AGN has been ambiguous. However, recently it was
observed to undergo a radio outburst which reveals a bright continuum
source (Argo et al. 2015), coincident with Chandra 2-8 keV emission
from one of the three point sources near the nucleus (<5"). This
confirms and pinpoints the X-ray position of the AGN. Comparisons of
the Chandra flux with the radio emission and other multiwavelength
luminosity indicators indicate that the X-ray flux is suppressed,
suggesting that it is absorbed by a high column of gas. A NuSTAR
observation for this object has been scheduled as part of our program.
The requested Chandra observation is essential to unambiguously
constrain the AGN and isolate it from other sources at <8 keV. When
combined with NuSTAR, we will then be able to accurately characterise
the 0.5-30 keV spectrum of the AGN for the first time.
New Horizons Encounter with Pluto
PI: McNutt
Abstract: Current models of Pluto s extended atmosphere remain uncertain.
Applying knowledge gained from studying cometary X-ray emission,
Chandra ACIS-S photometric imaging of X-rays produced by CXE between
the solar wind and Pluto s atmosphere addresses both the atmospheric
density and the interaction of the solar wind with the extended
Plutonian atmosphere. An exploratory measurement on 24 February 2014
for 35 ksec provided a marginal X-ray emission signal from Pluto given
the low solar wind flux at the time. By increasing the observing time
by a factor of 4 (to 140 ksec), the tentative Cycle 15 detection will
be verified or much tighter upper limits on the neutral gas escape
rate will be determined. The timing of the observation is fixed in
time to coincide with the encounter of the New Horizons (NH)
spacecraft with Pluto, a unique in situ event in solar system
exploration. Chandra provides a unique, global and contemporaneous
X-ray measurement of the system.
New Horizons Encounter with Pluto
PI: McNutt
Abstract: Current models of Pluto s extended atmosphere remain uncertain.
Applying knowledge gained from studying cometary X-ray emission,
Chandra ACIS-S photometric imaging of X-rays produced by CXE between
the solar wind and Pluto s atmosphere addresses both the atmospheric
density and the interaction of the solar wind with the extended
Plutonian atmosphere. An exploratory measurement on 24 February 2014
for 35 ksec provided a marginal X-ray emission signal from Pluto given
the low solar wind flux at the time. By increasing the observing time
by a factor of 4 (to 140 ksec), the tentative Cycle 15 detection will
be verified or much tighter upper limits on the neutral gas escape
rate will be determined. The timing of the observation is fixed in
time to coincide with the encounter of the New Horizons (NH)
spacecraft with Pluto, a unique in situ event in solar system
exploration. Chandra provides a unique, global and contemporaneous
X-ray measurement of the system.
PI: Heinz
Abstract: In June 2013, V404 Cyg went into a bright outburst after 26 years of
quiescence. The source flux is now in decline. Swift observations
reveal the presence of four bright rings, caused by scattering off of
interstellar dust clouds between us and the source. This is only the
third fully resolved echo of a Galactic source. Because the distance
to the source is accurately known, it is possible to perform precision
dust tomography and calibrate the use of dust echoes as distance
measure. To reach the required sensitivity, avoid cross contamination
with dispersed spectra of the dust scattering halo, and be able to
accurately model and remove cosmic and particle backgrounds, gratings
observations cannot be used for this science, and we ask for a 30ksec
full frame imaging observation.
New Horizons Encounter with Pluto
PI: McNutt
Abstract: Current models of Pluto s extended atmosphere remain uncertain.
Applying knowledge gained from studying cometary X-ray emission,
Chandra ACIS-S photometric imaging of X-rays produced by CXE between
the solar wind and Pluto s atmosphere addresses both the atmospheric
density and the interaction of the solar wind with the extended
Plutonian atmosphere. An exploratory measurement on 24 February 2014
for 35 ksec provided a marginal X-ray emission signal from Pluto given
the low solar wind flux at the time. By increasing the observing time
by a factor of 4 (to 140 ksec), the tentative Cycle 15 detection will
be verified or much tighter upper limits on the neutral gas escape
rate will be determined. The timing of the observation is fixed in
time to coincide with the encounter of the New Horizons (NH)
spacecraft with Pluto, a unique in situ event in solar system
exploration. Chandra provides a unique, global and contemporaneous
X-ray measurement of the system.
PI: Neilsen
Abstract: In May 1989, the black hole V404 Cyg exhibited some of the brightest,
most dramatic variability ever seen from a Galactic X-ray binary. The
spectacular variability, lasting only 1-2 weeks, was followed by a
slow 6 month decay. Given the extremity of the outburst and the
significant deviations from canonical BH behavior, little is
understood about the physics of this remarkable system. A new outburst
began on June 16, but how closely will V404 Cyg follow the BH track
after its initial fireworks have ended? P Cygni profiles are seen in
the optical (ATel 7669). Will V404 Cyg produce a massive X-ray disk
wind? A strong variable iron line has also been reported (ATel #7694).
We propose two 40 ks observations (~2 orbital periods), in 20-30 and
40-60 days, to study the variable Fe line and search for X-ray
absorption diagnostics of the growing wind during the later portions
of the outburst. Even on our time scale, we expect fluxes near 0.25-1
Crab and a factor of ~5 variability.
PI: King
Abstract: V404 Cyg has gone into outburst(ATEL 7646..7663). The light curve from
its last (1989) outburst was characterized by a dramatic rise starting
May 23 until May 30, where it then plummeted in X-ray flux (Zycki99),
unusual for X-ray binaries. The outburst was also very close to its
Eddington limit (Tanaka89, Zycki99). Super-Eddington accretion can
explain the bizarre light curve behavior, as ejection of accreting
shells driven by radiation pressure may have disrupted the disk and
caused the dramatic decrease in flux. V404 is now in outburst, and we
will examine its behavior with unprecedented spectral resolution with
the Chandra HETG.Based on our previous work with J17091-3624 (King14),
GRO 1655-40 (Miller08), and GRS 1915+105 (Miller in prep), we find
that 40 ksec is sufficient at detecting lines at >3 sigma. Finding
evidence for winds (or lack there of) will have vital implications for
outflow generation during Eddington accretion phases, feedback, and
growth of black holes.
PI: King
Abstract: V404 Cyg has gone into outburst(ATEL 7646..7663). The light curve from
its last (1989) outburst was characterized by a dramatic rise starting
May 23 until May 30, where it then plummeted in X-ray flux (Zycki99),
unusual for X-ray binaries. The outburst was also very close to its
Eddington limit (Tanaka89, Zycki99). Super-Eddington accretion can
explain the bizarre light curve behavior, as ejection of accreting
shells driven by radiation pressure may have disrupted the disk and
caused the dramatic decrease in flux. V404 is now in outburst, and we
will examine its behavior with unprecedented spectral resolution with
the Chandra HETG.Based on our previous work with J17091-3624 (King14),
GRO 1655-40 (Miller08), and GRS 1915+105 (Miller in prep), we find
that 40 ksec is sufficient at detecting lines at >3 sigma. Finding
evidence for winds (or lack there of) will have vital implications for
outflow generation during Eddington accretion phases, feedback, and
growth of black holes.
luminous X-ray pulsar?
PI: Brightman
Abstract: Swift XRT monitoring of M82 has shown that the X-ray emission from the
galaxy has increased by a factor of ~4 from its usual 2-10 keV
luminosity of 1x10^40 ergs/s. Previous flux increases have been
attributed to the intermediate mass black hole candidate, X-1,
entering the thermal disk-dominated state (Feng & Kaaret 2010),
however the neighboring source, X-2, recently identified as an ultra
luminous pulsar (Bachetti et al 2014) has also been known to reach
10^40 ergs/s. At 4 arcsec separation, only Chandra can tell which
source is causing the current brightening. With an off-axis
observation with a sub array of pixels to mitigate pile-up, valuable
spectral constraints will be provided by Chandra. Furthermore, if this
Chandra observation is approved, we will trigger a NuSTAR ToO to
measure the high energy spectrum of the source, whichever it may be.
evolutionary stages of Massive Stars
PI: MARGUTTI
Abstract: The mass-loss history of massive stars is one of the least understood
and yet fundamental aspects of stellar evolution. HOW and WHEN do
massive stars lose their hydrogen envelopes? This central, yet
still-open question motivates our investigation. Here we ask for
Chandra observations to map the evolution of the transient SNhunt275
on its way to become a Supernova. SNhunt275 was identified in 2013 as
a luminous outburst from a stellar object in NGC2770. The same star
gave rise to a luminous display earlier this year and recently
underwent a drastic re-brightening and spectral evolution which likely
prelude to a major explosion, in close similarity to SN2009ip. Our
primary goal is to constrain the density and location of the material
in the immediate environment of SNhunt275, and hence the mass-loss
history of its stellar progenitor over the last ~100 yrs. This is only
possible through deep X-ray observations that sample the emission
arising from the shock interaction with the medium.
evolutionary stages of Massive Stars
PI: MARGUTTI
Abstract: The mass-loss history of massive stars is one of the least understood
and yet fundamental aspects of stellar evolution. HOW and WHEN do
massive stars lose their hydrogen envelopes? This central, yet
still-open question motivates our investigation. Here we ask for
Chandra observations to map the evolution of the transient SNhunt275
on its way to become a Supernova. SNhunt275 was identified in 2013 as
a luminous outburst from a stellar object in NGC2770. The same star
gave rise to a luminous display earlier this year and recently
underwent a drastic re-brightening and spectral evolution which likely
prelude to a major explosion, in close similarity to SN2009ip. Our
primary goal is to constrain the density and location of the material
in the immediate environment of SNhunt275, and hence the mass-loss
history of its stellar progenitor over the last ~100 yrs. This is only
possible through deep X-ray observations that sample the emission
arising from the shock interaction with the medium.
nature
PI: Lutovinov
Abstract: We propose to perform a snapshot observation of the transient source
2S1553-542, which demonstrated an outburst last three months. The
current outburst is a third one only detected from this source since
1975 (the second one was in 2007). Previously the source nature was
tentatively proposed as a X-ray pulsar (pulse period 9.3 sec) in the
Be binary system due to the outbursts activity. But no optical
counterpart was established till the moment. One of main reasons of
this is a lack of knowledge of exact coordinates of the source. The
proposed observations at the outburst decay stage is a unique chance
to determine the source coordinates with a high precision, to perform
follow-up observations in optical and infrared wavebands and establish
its nature. Additionally, based on the results of spectral analysis we
will determine if the source is still accreting at low level or we
observe the heated neutron star.
Luminosities.
PI: Patruno
Abstract: The accreting pulsar (AMXP) SAX J1808.4-4658 is now in outburst (ATel
#7346). Seven more have been observed, with pulsations at 401 Hz.
Recently, we made two key discoveries: i. the accretion disk of SAX
J1808 might be truncated close to the co-rotation radius (i.e., where
plasma co-rotates with the neutron star) even at the lowest
luminosities (1e33 erg/s). We suspect that this is due to a new type
of accretion flow: the "trapped dead disk" (see
Patruno+2015,arXiv:1504.05048). ii. we have phase-connected *all*
pulsations observed by RXTE (Patruno+, in prep.), having now a 13 year
baseline. This is unprecedented for any AMXP. If we phase connect *one
more outburst* we can constrain the proper motion and variations of
the semi-major axis for the fisrt time. We'd like to find pulsations
at low luminosities (during reflares) and conclusively determine
whether a disk extends down the co-rotation radius. Then phase connect
these pulsations with our previous 13-yr baseline.
PI: Berger
Abstract: Understanding the collimation of short GRB jets is critical for
inferring their true energy release and event rate. This not only
impacts our understanding of these explosive events (e.g. energy
extraction and dissipation), but given their likely association to
neutron star binary mergers also feeds into the expected Advanced LIGO
merger rate, and the expected brightness of Advanced LIGO
electromagnetic counterparts. At the present only 4 short GRB jet
opening angle measurements have been made (by our group using Chandra
and XMM), so every additional measurement will have an impact on the
opening angle distribution. Here we request a single 25 ksec Chandra
observation on a timescale of about 7 days post-burst to measure the
decline rate relative to the XRT early data and hence to determine the
jet opening angle. The detection of a break will indicate a jet of
5-10 deg, while a non-detection will point to a broad outflow with >10
deg.
X-ray binary
PI: Degenaar
Abstract: In low-mass X-ray binaries (LMXBs) a neutron star or a black hole
accretes matter from a low-mass companion star via an accretion disk.
Outflows in the form of X-ray disk winds and radio jets are
universally linked to the accretion process. During low-luminosity
(<1E37 erg/s) "hard" X-ray states radio jets prevail, whereas disk
winds are only seen during high-luminosity (>1E37 erg/s) "soft"
states. Disk winds are now routinely detected and studied in black
hole LMXBs, but much less is known about such winds in neutron star
LMXBs, which are often fainter. Here we propose to seize the rare
opportunity to study the disk wind in a transient neutron star LMXB,
which is currently exhibiting an outburst and entered an X-ray bright
soft state on April 4th. Swift/XRT observations reveal ionized
absorption features at high (>5 keV) energies that are indicative of a
disk wind in this system. Only with the unprecedented spectral
resolution of Chandra/HETG can these features studied in detail.
PI: Orio
Abstract: GK Persei is the "all-in-one" white dwarf interacting binary. It can
be classified as a nova (outburst in 1901), as a symbiotic because of
the red giant companion, as a magnetic system (it is an intermediate
polar or IP), as a dwarf nova (every ~2 years it has repeated
disk-instability-related outbursts) and even as a "mini-supernova
remnant" (it has just "made the news" again, with a Chandra
press-release, because of its luminous at-all-wavelengths, and still
expanding shell ejected in 1901). In March a new dwarf- nova-like
outburst started and we have been monitoring it with Swift. The count
rate in the Swift XRT varies between about 1 and about 2 cts/s (ATels
7246, 7248) and the Swift spectrum indicates a main component of the
X-ray flux, a thermal one, that peaks at energy well above the Swift
range - for this reason we have applied also for NuSTAR time. However,
only grating spectra reveal the full physical picture: we plan to
study how GK Per is evolving.
PI: Schneider
Abstract: In Oct 2014 the well studied young star RW Aur A was unexpectedly
obscured by the tidally disrupted disk of its close but resolved
binary companion RW Aur B (Petrov et al. 2015,
arxiv.org/abs/1503.04158). Such events are extremely rare and provide
us with a chance to directly measure the gas-to-dust ratio of
protoplanetary disk material. We can measure this ratio by comparing
the differences in X-ray absorption (caused by gas) and optical
absorption (caused by dust) before and during the obscuration event.
So far, estimates are highly model dependent; this observation offers
an actual measurement to tightly constrain planet formation models
that currently suffer from our ignorance of reliable disk gas masses.
Such dimming events are short (the only known other such event lasted
180 days) and unpredictable and thus require quick follow-up
observations when seen in a key system such as RW Aur, where the
bright state is already well characterized at optical and X-ray
wavelengths.
PI: Posselt
Abstract: The potential temperature (T) decline of the Central Compact Object
(CCO) in the Cas A SNR is important to probe fundamental physics via
the study of neutron star cooling. An exciting T-decline found from
GRADED(G)-mode observations is called into doubt by results from
subarray FAINT (F) observations. Possible reasons are pile-up and
grade migration in the G-mode. Cross-calibration of the different
instrument setups was not possible previously due the poorly known
spatial distribution of the filter contaminant. We propose a
calibration subarray F observation of Cas A with the CCO centered at
exactly the same chip position as in a contemporaneous G-mode
observation. This will allow us to obtain a contaminant-independent
assessment of the G-mode effects on the CCO spectrum. With this, one
can re-calibrate the past 19 G-mode data sets. Such a
cross-calibration will be also useful to the general X-ray community.
PI: Burrows
Abstract: On March 1, 2015, Swift responded to a strong hard X-ray flare (1000
cps) in the direction of M31, lasting 20 s. It was initially
classified as a possible GRB and given the name GRB 150301C. The lack
of a soft X-ray counterpart was very puzzling. Further analysis showed
a very weak counterpart at about 100 s after the trigger, but this
faded rapidly. The only sources similar in terms of BAT to XRT flux
ratio are short GRBs and SGR flares, both of which are much shorter in
the duration of the hard X-ray burst than this object. XRT found a
single very faint, but fading, object within the BAT error circle,
coincident with a known X-ray source found in an XMM survey of M31:
[PFH2005] 622. Within the XMM source error circle there are 3 optical
sources. We request a 20 ks Chandra observation to localize the
position of the [PFH2005] 622 and to determine whether it is currently
brighter than the XMM flux of 6.9E-15 cgs.
unprecidented low UV flux state
PI: Grupe
Abstract: We have monitored the Narrow Line Seyfert 1 galaxy WPVS 007 with Swift
since 9.5 years. During this time it has shown a gradual decline in
its UV flux. While this is somewhat expected, because WPVS 007 has
shown an evolution of broad absorption lines seen by HST (Leighly et
al. 2009), in the February 21 Swift observation we noticed a sudden
drop in it's UV M2 magnitude/flux. A new Swift observation on February
28 not only confirmed this low state, it even showed that the UV flux
had dropped even more to an unprecedented low state in the UV since we
have started monitoring WPVS 007 in October 2005! We were just grated
to continue with weekly monitoring with Swift for the next few weeks
to follow the UV flux. However, we need to compare this UV flux with
the current flux in X-rays. While WPVS 007 showed X-ray flaring in
2010 and 2011, stacking Swift data since 2011 suggest that it has
decayed also in X-rays. WPVS 007 is a link between BAL QSOs and NLS1.
PI: Petroff
Abstract: A new class of bright, isolated, potentially extragalactic pulses
called fast radio bursts (FRBs) is emerging in radio surveys. Only a
handful of sources are known to-date. No host galaxies or progenitors
have been identified, and some of the population s most basic
properties are still being determined. The only FRB ever followed-up
at X-ray wavelengths showed no transient X-ray emission in
observations beginning 8 hours after the event. Rapid response is
needed to determine if an X-ray counterpart exists. This would be the
first multi-wavelength detection of an FRB. Swift is unable to make
these observations as the source may be too faint for Swift and at the
moment the Swift telescope is moon constrained and cannot take
observations on this source.
wind accretion onto a NS
PI: Oskinova
Abstract: We propose a direct experiment to probe the theory of HMXBs. Currently
we conduct the HST survey of HMXBs (PI Oskinova). The HMXB 4U1700-38
will be observed on Feb 22. From the analysis of the STIS spectra we
will determine mass-loss rate, wind velocity and clumping in the donor
star. We need simultaneously HETGS data to test how X-rays respond to
the changes in the wind. Such experiment was never done before. The
HETGS spectra will probe absorption, variability, and emission lines.
Simultaneous X-ray and UV observations will yield an unprecedented
insight on the processes operating in HMXBs. Chandra observed
4U1700-37 in 2003 (id 657) but in different phase. The RGS spectrum is
relatively featureless, while emission lines are prominent in the
HEGTS range. The HEG+MEG count rate varies erratically between 0.2 cps
and 20 cps. We request 15 ks to fully characterize the X-ray behavior.
Zero order will be most likely piled up, the +1 and -1 order will be
fully useful.
PI: Levan
Abstract: Swift J123205.1-1056 is a short, soft outburst detected by Swift. In
the error box is an AGN at z=0.134. CXO observations reveal a second
X-ray source on the stellar field of this AGN. If associated (the
probability of chance alignment is low) it has L_X ~ 1e43 ergs/s. This
luminosity suggests either an "afterglow"-like event, or if persistent
a hyperluminous, non-nuclear X-ray source. In the former case it is
possible given the softness of the burst that we may be observing a
tidal flare-like event, in which case a WD-IMBH disruption within a
globular cluster in the galaxy is possible (this is a luminous galaxy
that may contain a high specific frequency of globular clusters, but
has little/no star formation). A repeat of the earlier CXO
observations will allow us to assess variability in the source. Strong
variability would point to a transient event, most likely related to
the gamma-rays. No variability would imply a persistent HLX, but would
still be of considerable interest.
J123205.1-105602
PI: Troja
Abstract: Swift recently triggered on a short duration transient dubbed Swift
J123205.1-105602. Its unusual soft spectrum seems not to be consistent
with a typical short-hard GRB, and its nature is still not well
understood. An optical counterpart was found at the edge of a nearby
galaxy at redshift z=0.093, placing this event within the sensitivity
of advanced LIGO/Virgo. The X-ray emission detected by the Swift/XRT
appears constant, which is also unusual for a typical GRB afterglow.
We request rapid Chandra observations in order to: 1) accurately
localize the X-ray transient, robustly associate it to the optical
counterpart, and eventually detect possible contaminating sources
within the XRT point spread function; 2) constrain the spectral shape
in order to better understand the nature of this object (e.g. neutron
star merger, shock breakout, tidal disruption event).
PI: MARGUTTI
Abstract: The mass-loss history of massive stars is one of the least understood
yet fundamental aspects of stellar evolution. HOW and WHEN do massive
stars lose their hydrogen envelopes? This central, still-open question
motivates our present investigation. Here we ask for a continuation of
our Chandra program to map the unique situation of the interaction of
a hydrogen-stripped supernova 2014C with a thick, hydrogen-rich shell
ejected by the progenitor star, as part of our multi-wavelength (mm to
gamma-rays) follow-up. Our primary goal is to constrain the density
and location of the material in the immediate environment of SN2014C,
and hence the mass-loss history of its stellar progenitor.
PI: MARGUTTI
Abstract: The mass-loss history of massive stars is one of the least understood
yet fundamental aspects of stellar evolution. HOW and WHEN do massive
stars lose their hydrogen envelopes? This central, still-open question
motivates our present investigation. Here we ask for a continuation of
our Chandra program to map the unique situation of the interaction of
a hydrogen-stripped supernova 2014C with a thick, hydrogen-rich shell
ejected by the progenitor star, as part of our multi-wavelength (mm to
gamma-rays) follow-up. Our primary goal is to constrain the density
and location of the material in the immediate environment of SN2014C,
and hence the mass-loss history of its stellar progenitor.
PI: MARGUTTI
Abstract: The mass-loss history of massive stars is one of the least understood
yet fundamental aspects of stellar evolution. HOW and WHEN do massive
stars lose their hydrogen envelopes? This central, still-open question
motivates our present investigation. Here we ask for a continuation of
our Chandra program to map the unique situation of the interaction of
a hydrogen-stripped supernova 2014C with a thick, hydrogen-rich shell
ejected by the progenitor star, as part of our multi-wavelength (mm to
gamma-rays) follow-up. Our primary goal is to constrain the density
and location of the material in the immediate environment of SN2014C,
and hence the mass-loss history of its stellar progenitor.
PI: Miller
Abstract: ASASSN-14li is the best possible tidal disruption flare (TDF). Its
host galaxy is at z = 0.02, whereas the prior X-ray bright event
(Swift J16444) was at z = 0.35. The position of this transient is
within 0.04" of the host galaxy. The source was previously quiescent,
and the optical spectrum - both before and after the flare - are
inconsistent with an active Seyfert nucleus. The most recent flux (Dec
2) measured with the Swift XRT is 2 E-11 erg/cm2/s in the 0.2-2.0 keV
band. A moderately deep integration will give a spectrum that should
compare well with Seyfert spectra. There is only weak galactic
absorption along the line of sight to this source (few E+20 cm^-2),
meaning that the low temperature emission (kT = 66 eV) will give an
excellent spectrum at long wavelengths. If the disrupted gas is
illuminated by the central engine, it is reasonable to expect
optically thin line emission on top of a thermal continuum. Please
see: http://www.astronomerstelegram.org/?read=6777
PI: Miller
Abstract: ASASSN-14li is the best possible tidal disruption flare (TDF). Its
host galaxy is at z = 0.02, whereas the prior X-ray bright event
(Swift J16444) was at z = 0.35. The position of this transient is
within 0.04" of the host galaxy. The source was previously quiescent,
and the optical spectrum - both before and after the flare - are
inconsistent with an active Seyfert nucleus. The most recent flux (Dec
2) measured with the Swift XRT is 2 E-11 erg/cm2/s in the 0.2-2.0 keV
band. A moderately deep integration will give a spectrum that should
compare well with Seyfert spectra. There is only weak galactic
absorption along the line of sight to this source (few E+20 cm^-2),
meaning that the low temperature emission (kT = 66 eV) will give an
excellent spectrum at long wavelengths. If the disrupted gas is
illuminated by the central engine, it is reasonable to expect
optically thin line emission on top of a thermal continuum. Please
see: http://www.astronomerstelegram.org/?read=6777
PI: Heida
Abstract: Intermediate mass black holes are crucial as building blocks for
supermassive BHs, but observational evidence for their existence is
still scarce. The brightest ULXs may be good IMBH candidates: the
strongest case is ESO 243-49 HLX-1 (Farrell et al. 2009), an X-ray
source that reaches a luminosity of more than 10E42 erg/s. It is
thought to host a BH of ~20,000 solar masses. Up until now, HLX-1 is
the only known object of its kind. Most candidate ULXs with comparable
luminosities have turned out to be background AGN. Finding more HLX-1
like objects would be an important step forward in the search for
IMBHs. We have investigated the X-ray source CXOJ122518.6+144545
(J1225; Jonker et al. 2010) with Chandra. It was found in an
observation from 2008, at a luminosity of ~2E41 erg/s, making it the
second most luminous ULX after HLX-1. We did not detect the source in
November 2012 and in April and July 2014, but in our last observation
on November 20 it was again visible at ~5E40 erg/s.
PI: Heida
Abstract: Intermediate mass black holes are crucial as building blocks for
supermassive BHs, but observational evidence for their existence is
still scarce. The brightest ULXs may be good IMBH candidates: the
strongest case is ESO 243-49 HLX-1 (Farrell et al. 2009), an X-ray
source that reaches a luminosity of more than 10E42 erg/s. It is
thought to host a BH of ~20,000 solar masses. Up until now, HLX-1 is
the only known object of its kind. Most candidate ULXs with comparable
luminosities have turned out to be background AGN. Finding more HLX-1
like objects would be an important step forward in the search for
IMBHs. We have investigated the X-ray source CXOJ122518.6+144545
(J1225; Jonker et al. 2010) with Chandra. It was found in an
observation from 2008, at a luminosity of ~2E41 erg/s, making it the
second most luminous ULX after HLX-1. We did not detect the source in
November 2012 and in April and July 2014, but in our last observation
on November 20 it was again visible at ~5E40 erg/s.
the environment around a Type Iax SN
PI: MARGUTTI
Abstract: PSN J12215757+0428185 is a young Type Iax SN. It exploded in M61 and
it is the nearest Type Iax ever found. Here we ask for 20ks of Chandra
observations to constrain the density of the very close environment,
shaped by the mass-loss history of the progenitor system before the
explosion. This observation will allow us constrain the nature of the
progenitor system of this new kind of stellar explosions.
PI: Feng
Abstract: NGC 247 is a dwarf or intermediate spiral galaxy at a distance of 3.4
Mpc. Past observations suggest that there was no activity of the
nuclear black hole. We conducted an XMM observation of NGC 247 on 2014
July 1, which serendipitously detected a bright X-ray source
coincident with the nuclear position (within 2 arcsec) with a
luminosity of 2E39 erg/s in 0.3-10 keV. The most recent observation
before that one was made on 2011 Feb 1 with Chandra. There was no
detection in the nuclear region, giving an upper limit of 1E37 erg/s.
If the new X-ray source is indeed due to the nuclear black hole
activity, its sudden brightening suggests that it may have tidally
disrupted a star some time between 2011 and 2014, or start to accrete
a stream of gas at a low rate. Either will be of great interest due to
its rarity and the small distance. A sub-arcsecond position accuracy
is needed to determine if the X-rays arise from the nucleus.
PI: Gallo
Abstract: The target of this request is a newly discovered 30,000 solar mass
black hole candidate. As part of a follow-up spectroscopic campaign of
SDSS dwarf galaxies with optical signatures of AGN activity (Reines+
2014, ApJ, 775, 24), we recently acquired high resolution
Magellan/MagE spectra of a ~10^9 solar mass galaxy with narrow line
signatures of an AGN. The MagE spectrum clearly reveals the presence
of a broad H_alpha component that was only marginally detected in the
SDSS spectrum. Using standard virial techniques, the measured FWHM and
luminosity correspond a black hole mass of 30,000 solar masses. The
galaxy is a face-on disky dwarf with low Galactic absorption at a
distance of ~100 Mpc. We request 20 ksec with ACIS-S. In conjunction
with the optical diagnostics, the detection of a >10^40 erg/s, point
like X-ray source at a position consistent with the galaxy nucleus
would provide compelling evidence that this dwarf galaxy hosts the
smallest supermassive black hole reported to date.
1935+2154
PI: Rea
Abstract: Chandra observed SGR 1935+2154's outburst on the 15th and 28th of July
2014 for 9ks (ACIS-S, TE-mode) and 75ks (ACIS-S CC-mode). We detected
for the first time highly significant, >10sigma, pulsations at a
period of 3.24498(1) s (1 sigma c.l.), confirming it as a magnetar
candidate. Folding directly with this period the first observation we
detect the signal at a lower significance, deriving a period
derivative upper limit of about 2x10^-10 s/s was inferred. Swift
cannot see the signal because the source is too faint. We have
activated our XMM-Newton ToO program to keep monitoring the source,
but the XMM visibility will start on September 27th. We ask here for a
30ks DDT observation with ACIS-S CC-mode around late August to keep
the phase-coherence of our timing solution. This will allow the
determination of the period derivative of this new magnetar, crucial
to define the dipolar surface magnetic field of this object, then
identifying it as a highly-dipolar or low-dipolar magnetar.
wavelengths
PI: Nucita
Abstract: EXORs are pre-main sequence stars that show recurrent luminosity
changes of short duration superposed to longer quiescence periods, see
e.g. Audard et al. 2014. Although a general consensus exists about the
nature of such outbursts (i.e. events of enhanced magnetospheric
accretion from the circumstellar disk), the physical mechanisms
regulating the outbursts and how these latter affect the circumstellar
disk structure and its evolution are not clarified yet. We recently
started an observational programme on this class of objects (EXORCISM,
EXOR OptiCal and Infrared Systematic Monitoring, Antoniucci et al.
2013). Optical and near-IR studies of EXORs rapidly increased in the
last decade but little is known about the X-ray properties, in
particular whether X-rays come from the corona of the star (being in
this case unaffected by the outbursts) or, conversely, originate in
accretion events.
PI: Bordas
Abstract: PSR B1259-63 is undergoing a flare emission in gamma-rays (ATel
#6204). Such a flare was observed for the first time in 2010,
accounting for almost 100% of the pulsar spin-down power. No flare
counterpart at higher/lower energies was observed at that time,
although the unexpected nature of the event made its MWL coverage
rather poor. We ask for Chandra DDT observations of PSR B1259-63 to
search for the flare X-ray counterpart (2 pointings x 5ksec each
during the next nights) and to monitor itsX-ray/TeV evolution (2
pointings x 5 ksec = 20 ksec from June 16th), in which H.E.S.S. will
observe the source simultaneously. The nature of the GeV flare and its
connection to the X-ray/TeV emission observed during PSR B1259-63
periastron passage makes simultaneous observations crucial. Next
Cherenkov observations will not be possible until 2021. No other X-ray
observatories are available for the requested dates (Swift XRT may not
be available next nights, see GCN 16349).
PI: Bordas
Abstract: PSR B1259-63 is undergoing a flare emission in gamma-rays (ATel
#6204). Such a flare was observed for the first time in 2010,
accounting for almost 100% of the pulsar spin-down power. No flare
counterpart at higher/lower energies was observed at that time,
although the unexpected nature of the event made its MWL coverage
rather poor. We ask for Chandra DDT observations of PSR B1259-63 to
search for the flare X-ray counterpart (2 pointings x 5ksec each
during the next nights) and to monitor itsX-ray/TeV evolution (2
pointings x 5 ksec = 20 ksec from June 16th), in which H.E.S.S. will
observe the source simultaneously. The nature of the GeV flare and its
connection to the X-ray/TeV emission observed during PSR B1259-63
periastron passage makes simultaneous observations crucial. Next
Cherenkov observations will not be possible until 2021. No other X-ray
observatories are available for the requested dates (Swift XRT may not
be available next nights, see GCN 16349).
environment of a GRB from the early Universe (z~6)
PI: MARGUTTI
Abstract: Among the most important parameters to constrain the GRB physics (both
jet launching mechanism and progenitor) are the energy scale, jet
geometry and the burst environment. Those can only be estimated
through broadband modeling of the late afterglow emission (radio to
X-rays). Of particular interest is to constrain the properties of the
z>6 population of GRBs that sample the star formation in the early
Universe (<1Gyr), and understand if they have unique properties when
compared to the overall population. This can only be done if reliable
estimates of the intrinsic properties of high-z GRBs and their
environments are available. Only 3 GRBs have been spectroscopically
confirmed at z>6 (050904, 080913, 090423). GRB140515A at z=6.32 offers
the opportunity to expand the sample. Chandra data acquired at
t+10days (after the flares) are crucial to map the spectrum above the
cooling frequency, thus enabling us to determine the true energy, jet
opening angle and environment of a rare z>6 GRB.
PI: Miller
Abstract: Observations of GRO J1744-28 with Chandra and NuSTAR reveal confusing
but potentially very revealing structure within the Fe K region. The
complex is either due to a very odd combination of charge states
within cospatial gas, or it represents double-horned emission line
structure from a truncated accretion disk. This is a significant
challenge to basic ideas of accretion in low-mass X-ray binaries, HETG
resolution can solve it.
PI: Miller
Abstract: Observations of GRO J1744-28 with Chandra and NuSTAR reveal confusing
but potentially very revealing structure within the Fe K region. The
complex is either due to a very odd combination of charge states
within cospatial gas, or it represents double-horned emission line
structure from a truncated accretion disk. This is a significant
challenge to basic ideas of accretion in low-mass X-ray binaries, HETG
resolution can solve it.
J1744-28
PI: Kennea
Abstract: Discovered Dec 1995, GRO J1744-28, AKA "The Bursting Pulsar", is one
of only two known objects to exhibit Type-II X-ray bursts. That
outburst lasted ~6 months, and since it has remained in quiescence.
Recently a coordinated effort by Swift, MAXI and Fermi confirmed GRO
J1744-28 to be in its first outburst in ~18 years. With Chandra we
entered the era of high resolution X-ray spectra, however Chandra has
only observed GRO J1744-28 in quiescence, obtaining a very poor
spectrum. ASCA observations (Nishiuchi et al., 1999) detected a 6.7
keV Iron line feature, which is strongly detected in new observations
by Swift. However, the poor spectral resolution of ASCA and XRT do not
allow us to discern the real nature of this feature. With such high
accretion rate, we might expect that the line complex is a blend of
neutral and high ionized lines from disk wind. Only Chandra HETG
observations have the sufficient resolution to pin down the nature of
the X-ray emission lines in GRO J1744-28.
B1259-63/LS 2883
PI: Pavlov
Abstract: PSR B1259-63/LS 2883 is the famous eccentric gamma-ray binary
(Pbin=3.4 yr, e=0.87) in which a pulsar orbits a massive O-type star.
Using ACIS observations of 2011 December 17 and 2013 May 19, 62 ks
each, we unexpectedly detected an extended (of about 4'' size)
structure, apparently moving away from the binary with v = 0.05c
(arXiv:1312.2654). Such a moving X-ray nebula has never been seen
before. An additional observation before 2014 January 30 is needed to
distinguish between two different interpretations of the extended
emission: (1) a fast-moving cloud of relativistic electrons loaded
with a large amount of baryonic matter; (2) a variable extrabinary
shock in the pulsar wind outflow. If (1) is correct, we will see the
cloud at the same position angle as in May 2013, while the shock would
be seen at a substantially different position angle (corresponding to
the orbital position change since May 2013; see
http://home.gwu.edu/~kargaltsev/B1259.html) if (2) is correct.
PI: MARGUTTI
Abstract: SN2014J has been recently discovered in M82, at a very close distance
of 3.7 Mpc. The spectra indicates a Type Ia supernova explosion. Type
Ia Supernovae have been employed as cosmic ladders to reveal the
accelerating Universe. In spite of their importance for Cosmology, a
key, fundamental question still remain open: Which stars are the
progenitors of these cosmic standards? We ask for deep X-ray
observations, to probe the environment around SN2014J down to
unprecedented limits. By timing the X-ray observations to the time of
the optical peak, and using the formalisms I developed in Margutti
2012 (ApJ 751 134) I will be able to probe densities as low as a few
d-10 Msun/yr (or a few particle/cm3), thus enabling us to distinguish
between symbiotic and double-degenerate progenitors. These limits
would be a factor 10 deeper than the any other limit presented in the
literature so far. It is also possible that this study will lead to
the first detection of X-ray radiation from a Type Ia SN.
uniquely suited test system
PI: Poppenhaeger
Abstract: The evaporation of exoplanetary atmospheres is thought to be driven by
high-energy irradiation. However, the actual mass loss rates are not
well constrained. Co-I Kipping has recently discovered that the star
KOI-314, an M1V dwarf at 65 pc distance, is orbited by two earth-sized
planets, the inner one of them rocky and the outer one gaseous (P_orb
= 14d and 23d). Other recent works have shown an abundance of small
rocky planets in very close orbits around their host stars, suggesting
that the stellar high-energy irradiation evaporates away gaseous
envelopes. KOI-314 is the first nearby system in which earth-sized
planets of both types are detected, allowing us to constrain the
efficiency of planetary evaporation if the stellar X-ray irradiation
is measured. We therefore propose a 10 ks Chandra ACIS-S pointing to
determine the stellar X-ray luminosity and hardness ratio. The
accuracy of the orbital solution decreases quickly due to
Transit-Timing Variations, which is why we ask for DDT.
B1259-63/LS 2883
PI: Pavlov
Abstract: PSR B1259-63/LS 2883 is the famous eccentric gamma-ray binary
(Pbin=3.4 yr, e=0.87) in which a pulsar orbits a massive O-type star.
Using ACIS observations of 2011 December 17 and 2013 May 19, 62 ks
each, we unexpectedly detected an extended (of about 4'' size)
structure, apparently moving away from the binary with v = 0.05c
(arXiv:1312.2654). Such a moving X-ray nebula has never been seen
before. An additional observation before 2014 January 30 is needed to
distinguish between two different interpretations of the extended
emission: (1) a fast-moving cloud of relativistic electrons loaded
with a large amount of baryonic matter; (2) a variable extrabinary
shock in the pulsar wind outflow. If (1) is correct, we will see the
cloud at the same position angle as in May 2013, while the shock would
be seen at a substantially different position angle (corresponding to
the orbital position change since May 2013; see
http://home.gwu.edu/~kargaltsev/B1259.html) if (2) is correct.
PI: Patruno
Abstract: On 2013 Dec 10 we have discovered with a Swift/XRT observation, that
the low mass X-ray binary (LMXB) XSS J12270-4859 has recently changed
state from a quiescent-LMXB into a new anomalous faint state with no
signatures of accretion (ATel #5647). An NTT optical observation
suggests a transition around December 2012 in the opposite direction
to that of the "missing link" PSR J1023+0038 (that switched from a
radio millisecond pulsar (MSP), into an LMXB, Stappers et al.2013,
Patruno et al. 2013). A MSP may therefore be now active in XSS J12270.
We are currently completing the analysis of Parkes data to search for
the putative MSP. The Swift/XRT shows a faint source (1e32-1e33
erg/s). We want now to characterize the spectral behaviour with a 30
ks Chandra pointing. If we do not detect radio pulsations Chandra can
potentially tell us if the pulsar (and pulsar wind) are on even if the
radio pulsar is undetectable (as our preliminary Parkes analysis seems
to suggest).
very unusual explosion: SN2013ge
PI: MARGUTTI
Abstract: Recent discoveries have shaken our current classification scheme of
supernova explosions. SN2013ge is such a case.The spectra we obtained
within 2 hours since discovery (on Nov 8th) revealed a very unusual
and blue continuum with no sign of H or He. Additionally, the
broadband light-curve of this transient showed an early blue peak
whose origin is unclear. Together, these findings place SN2013ge
outside ANY previously known SN category. We ask for a Chandra
observation to place a solid limit to the environment density (and
hence reveal the mass-loss history of the progenitor) and distinguish
between progenitor types. These observations will also allow us to
constrain the energy density in magnetic fields, a key but poorly
known parameter in SN shock physics. These observations are part of a
multi-wavelength program which includes optical, NIR (both photometry
and spectroscopy), UV and radio observations to obtain the best
constraints to what might represent a new type of SN explosion.
130925A
PI: Bellm
Abstract: GRB 130925A produced several emission episodes triggering Swift-BAT,
Fermi-GBM, and MAXI. The extraordinary length of this emission--over
10^4 seconds--would give GRB 130925A one of the highest total
durations ever observed for a gamma-ray burst. While the initial
bursting phase was similar to that of the the relativistic tidal
disruption event Swift J1644+57, starting at 10^4 seconds after the
trigger this event has entered a steady decay phase without new bursts
(www.swift.ac.uk/xrt_curves/00571830/). Its classification is thus
uncertain, as neither the long GRB class nor Swift J1644 provide
direct parallels. Our NuSTAR spectroscopy during the decay phase has
revealed evidence for a broad absorption feature never previously
observed for either GRB afterglows or for tidal disruption events.
Chandra observations will enable searches for lower-energy lines which
may constrain the ionization state of this unprecedented event.
PI: De Pasquale
Abstract: Follow-up observations by XRT, UVOT, and ground facilities show Swift
GRB130831A to be an interesting and unusual long GRB at z=0.48, with a
bright optical afterglow. The X-ray light curve of this event
(www.swift.ac.uk/xrt_curves/00568849) displays a rare extremely steep
break from a power-law decay of 1.1 to 5 at ~10^5 s. The standard
forward-shock (FS) fireball model cannot explain the steepness of this
break. Instead it is the signature expected from the spin-down
emission of a newly-born magnetar seen before in short GRBs (Rowlinson
et al. 2013), but only once so far in a long GRB (070110, but 130831A
is a far superior example because the break is much later and we have
better coverage at other wavelengths). With the magnetar emission now
gone, we can measure the FS emission at nu > nu_c (with Chandra; it's
too faint now for Swift) to infer the total energy imparted to the
ejecta and have the first ever measurement of the efficiency of a
magnetar as central engine of a long GRB.
PI: De Pasquale
Abstract: Follow-up observations by XRT, UVOT, and ground facilities show Swift
GRB130831A to be an interesting and unusual long GRB at z=0.48, with a
bright optical afterglow. The X-ray light curve of this event
(www.swift.ac.uk/xrt_curves/00568849) displays a rare extremely steep
break from a power-law decay of 1.1 to 5 at ~10^5 s. The standard
forward-shock (FS) fireball model cannot explain the steepness of this
break. Instead it is the signature expected from the spin-down
emission of a newly-born magnetar seen before in short GRBs (Rowlinson
et al. 2013), but only once so far in a long GRB (070110, but 130831A
is a far superior example because the break is much later and we have
better coverage at other wavelengths). With the magnetar emission now
gone, we can measure the FS emission at nu > nu_c (with Chandra; it's
too faint now for Swift) to infer the total energy imparted to the
ejecta and have the first ever measurement of the efficiency of a
magnetar as central engine of a long GRB.
PI: Berger
Abstract: GRB 130606A at z=5.91 is only the fourth burst at such high redshift
with detected X-ray, optical/near-IR, and radio emission. The data
quality across the spectrum exceeds that of all previous events,
thereby providing a unique opportunity to study the energy scale and
local environment of a massive star explosion in the first Gyr after
the Big Bang. This will allow us to compare the progenitors of the
most distant GRBs to their more typical cousins at redshifts of z~1-3.
The energy scale will shed light the the nature of the explosion,
while the local density will track mass loss from the progenitor prior
to its demise, a direct clue to its nature. Of particular interest is
a measurement of jet collimation that will provide a measure of the
true energy release; strong evidence for such a "jet break" requires
an achromatic break from radio to X-rays. We will combine the
requested Chandra observation with extensive radio and optical/near-IR
data to decipher the GRB properties.
PI: Roberts
Abstract: Although long predicted and searched for, a population of
intermediate-mass black holes (IMBHs) has yet to be detected in the
local Universe. We have recently published a small sample of luminous
ULXs that behave like IMBHs in the low/hard state (Sutton et al. 2012
MNRAS 423 1154). If they are in that state, we expect to see steady
radio jets; from these we can directly measure the black hole mass
using quasi-simultaneous X-ray & radio observations to place an object
on the fundamental plane (see e.g. Merloni et al. 2003 MNRAS 345
1057). In VLA follow-up of the sample an IMBH candidate in NGC 2276
was shown to sit at the centre of two extended radio lobes. We have
now been awarded European VLBI network (EVN) observations to attempt
to detect its radio core. Here we ask for quasi-simultaneous Chandra
observations, necessary to resolve the IMBH candidate from two nearby
(within ~5") ULXs and provide the X-ray data point that will allow us
to measure the mass of the black hole.
PI: Mathur
Abstract: Seyfert 1 galaxy Mrk 590 is presently in an unusual state. Its X-ray
soft-excess has disappeared, its optical continuum has practically
vanished, its optical broad emission lines have disappeared, and it
shows the presence of a relativistic outflow. Even the narrow emission
lines have changed. All these observations could be related to each
other, but were taken years apart. We have an approved DDT on HST to
check if the UV continuum and UV broad emission lines have also
vanished and we request contemporaneous Chandra DDT to look for the
presence/ absence of the soft-excess. Together they will help
understand the common underlying cause which could be low accretion
rate relative to Eddington. They will also answer some long-standing
questions in AGN physics such as: What is the origin of the
soft-excess? What is the origin of the broad emission line region? Mrk
590 provides us with an unique opportunity find the underlying physics
related to these apparently disparate phenomena.
PI: Kaaret
Abstract: Discovery (Reines et al. 2011, Nature, 470, 66) of a massive black
hole (MBH) in a star-forming dwarf galaxy has shed light on the
relation between MBHs and galaxy formation and evolution. Optical
observations of the star-forming dwarf galaxy NGC 404 suggest it hosts
a 4.5E5 solar mass BH. EVLA observations by Nyland et al. 2012
combined with archival Chandra data show a radio/X-ray source
consistent with a ~1E6 solar mass BH. We have approved European VLBI
Network (EVN) observations to image NGC 404 at 5 mas resolution,
enabling us to eliminate alternative interpretations (SNR, star
forming region). We request contemporaneous Chandra observations to
determine the X-ray state of the source. The source is too dim for
Swift and only Chandra will resolve the BH from surrounding diffuse
emission. In 15 ks, we expect 18 counts in the 2-10 keV band enabling
detection of hard X-ray emission from the BH.
PI: Papitto
Abstract: IGR J18245-2452 is a newly discovered X-ray transient located in the
globular cluster M28 (ATel #4925), which showed a thermonuclear type-I
X-ray burst proving its NS accreting nature (ATel #4959). Optical and
radio counterparts have been proposed (ATel #4981,5003) and a
separate Chandra TOO has been approved to check the source location.
We proposea 60 ks Chandra observation with the HRC to check for any
additional close-by sources in the crowded environment of the
cluster, and to study variability of its emission.
Polar Solar Wind
PI: Lisse
Abstract: For the 1st time since the 1996 discovery of cometary X-ray emission,
Chandra can characterize the solar wind in the heliosphere AUs above
the ecliptic plane using the very active Comet PANSTARRS (C/2011 L4).
At +83o latitude the comet will encounter the low density, low
ionization temperature polar solar wind, entirely lacking in O+8 ions,
deficient in O+7 ions, and rich in O+6 ions. The Chandra Comet
PANSTARRS observations will also extend the observed regime of CXE
emission to much lower wind densities and temperatures. The polar wind
should produce an ACIS-S spectrum with no OVIII charge exchange lines,
very weak OVII lines, and unusually strong OVI lines. Thus we will use
ACIS to search for weak CXE lines due to highly stripped CNFeMgNeSi
solar wind ions normally dominated by OVII and OVIII at 500-800 eV,
and detect OVI at 0.11 keV using the sensitivity of Chandra's HRC-I
camera to extremely soft x-rays. 3 identical visits are requested to
allow for solar wind variability.
Polar Solar Wind
PI: Lisse
Abstract: For the 1st time since the 1996 discovery of cometary X-ray emission,
Chandra can characterize the solar wind in the heliosphere AUs above
the ecliptic plane using the very active Comet PANSTARRS (C/2011 L4).
At +83o latitude the comet will encounter the low density, low
ionization temperature polar solar wind, entirely lacking in O+8 ions,
deficient in O+7 ions, and rich in O+6 ions. The Chandra Comet
PANSTARRS observations will also extend the observed regime of CXE
emission to much lower wind densities and temperatures. The polar wind
should produce an ACIS-S spectrum with no OVIII charge exchange lines,
very weak OVII lines, and unusually strong OVI lines. Thus we will use
ACIS to search for weak CXE lines due to highly stripped CNFeMgNeSi
solar wind ions normally dominated by OVII and OVIII at 500-800 eV,
and detect OVI at 0.11 keV using the sensitivity of Chandra's HRC-I
camera to extremely soft x-rays. 3 identical visits are requested to
allow for solar wind variability.
Polar Solar Wind
PI: Lisse
Abstract: For the 1st time since the 1996 discovery of cometary X-ray emission,
Chandra can characterize the solar wind in the heliosphere AUs above
the ecliptic plane using the very active Comet PANSTARRS (C/2011 L4).
At +83o latitude the comet will encounter the low density, low
ionization temperature polar solar wind, entirely lacking in O+8 ions,
deficient in O+7 ions, and rich in O+6 ions. The Chandra Comet
PANSTARRS observations will also extend the observed regime of CXE
emission to much lower wind densities and temperatures. The polar wind
should produce an ACIS-S spectrum with no OVIII charge exchange lines,
very weak OVII lines, and unusually strong OVI lines. Thus we will use
ACIS to search for weak CXE lines due to highly stripped CNFeMgNeSi
solar wind ions normally dominated by OVII and OVIII at 500-800 eV,
and detect OVI at 0.11 keV using the sensitivity of Chandra's HRC-I
camera to extremely soft x-rays. 3 identical visits are requested to
allow for solar wind variability.
Tidal Disruption Event Candidate
PI: Lin
Abstract: Stars approach a SMBH can be tidally disrupted and subsequently
accreted. Such kind of tidal disrupt events (TDEs) provide a unique
way to find and study inactive SMBHs and may also provide an important
mechanism of growing them. Only about twenty such candidates have been
reported. Following-up of such events is important to constrain their
long-term evolution to help to pin down their nature and strengthen
the TDE theory. TDEs show large dynamic ranges on timescales of years,
allowing to search for possible state transition to test whether
accretion onto SMBHs is similar to that in stellar-mass BH X-ray
binaries. We now need an immediate Chandra observation to confirm the
nuclear origin of a post-flare hard spectrum from our TDE candidate
which has very soft spectra at the flare peak.
Polar Solar Wind
PI: Lisse
Abstract: For the 1st time since the 1996 discovery of cometary X-ray emission,
Chandra can characterize the solar wind in the heliosphere AUs above
the ecliptic plane using the very active Comet PANSTARRS (C/2011 L4).
At +83o latitude the comet will encounter the low density, low
ionization temperature polar solar wind, entirely lacking in O+8 ions,
deficient in O+7 ions, and rich in O+6 ions. The Chandra Comet
PANSTARRS observations will also extend the observed regime of CXE
emission to much lower wind densities and temperatures. The polar wind
should produce an ACIS-S spectrum with no OVIII charge exchange lines,
very weak OVII lines, and unusually strong OVI lines. Thus we will use
ACIS to search for weak CXE lines due to highly stripped CNFeMgNeSi
solar wind ions normally dominated by OVII and OVIII at 500-800 eV,
and detect OVI at 0.11 keV using the sensitivity of Chandra's HRC-I
camera to extremely soft x-rays. 3 identical visits are requested to
allow for solar wind variability.
Polar Solar Wind
PI: Lisse
Abstract: For the 1st time since the 1996 discovery of cometary X-ray emission,
Chandra can characterize the solar wind in the heliosphere AUs above
the ecliptic plane using the very active Comet PANSTARRS (C/2011 L4).
At +83o latitude the comet will encounter the low density, low
ionization temperature polar solar wind, entirely lacking in O+8 ions,
deficient in O+7 ions, and rich in O+6 ions. The Chandra Comet
PANSTARRS observations will also extend the observed regime of CXE
emission to much lower wind densities and temperatures. The polar wind
should produce an ACIS-S spectrum with no OVIII charge exchange lines,
very weak OVII lines, and unusually strong OVI lines. Thus we will use
ACIS to search for weak CXE lines due to highly stripped CNFeMgNeSi
solar wind ions normally dominated by OVII and OVIII at 500-800 eV,
and detect OVI at 0.11 keV using the sensitivity of Chandra's HRC-I
camera to extremely soft x-rays. 3 identical visits are requested to
allow for solar wind variability.
Polar Solar Wind
PI: Lisse
Abstract: For the 1st time since the 1996 discovery of cometary X-ray emission,
Chandra can characterize the solar wind in the heliosphere AUs above
the ecliptic plane using the very active Comet PANSTARRS (C/2011 L4).
At +83o latitude the comet will encounter the low density, low
ionization temperature polar solar wind, entirely lacking in O+8 ions,
deficient in O+7 ions, and rich in O+6 ions. The Chandra Comet
PANSTARRS observations will also extend the observed regime of CXE
emission to much lower wind densities and temperatures. The polar wind
should produce an ACIS-S spectrum with no OVIII charge exchange lines,
very weak OVII lines, and unusually strong OVI lines. Thus we will use
ACIS to search for weak CXE lines due to highly stripped CNFeMgNeSi
solar wind ions normally dominated by OVII and OVIII at 500-800 eV,
and detect OVI at 0.11 keV using the sensitivity of Chandra's HRC-I
camera to extremely soft x-rays. 3 identical visits are requested to
allow for solar wind variability.
Polar Solar Wind
PI: Lisse
Abstract: For the 1st time since the 1996 discovery of cometary X-ray emission,
Chandra can characterize the solar wind in the heliosphere AUs above
the ecliptic plane using the very active Comet PANSTARRS (C/2011 L4).
At +83o latitude the comet will encounter the low density, low
ionization temperature polar solar wind, entirely lacking in O+8 ions,
deficient in O+7 ions, and rich in O+6 ions. The Chandra Comet
PANSTARRS observations will also extend the observed regime of CXE
emission to much lower wind densities and temperatures. The polar wind
should produce an ACIS-S spectrum with no OVIII charge exchange lines,
very weak OVII lines, and unusually strong OVI lines. Thus we will use
ACIS to search for weak CXE lines due to highly stripped CNFeMgNeSi
solar wind ions normally dominated by OVII and OVIII at 500-800 eV,
and detect OVI at 0.11 keV using the sensitivity of Chandra's HRC-I
camera to extremely soft x-rays. 3 identical visits are requested to
allow for solar wind variability.
Polar Solar Wind
PI: Lisse
Abstract: For the 1st time since the 1996 discovery of cometary X-ray emission,
Chandra can characterize the solar wind in the heliosphere AUs above
the ecliptic plane using the very active Comet PANSTARRS (C/2011 L4).
At +83o latitude the comet will encounter the low density, low
ionization temperature polar solar wind, entirely lacking in O+8 ions,
deficient in O+7 ions, and rich in O+6 ions. The Chandra Comet
PANSTARRS observations will also extend the observed regime of CXE
emission to much lower wind densities and temperatures. The polar wind
should produce an ACIS-S spectrum with no OVIII charge exchange lines,
very weak OVII lines, and unusually strong OVI lines. Thus we will use
ACIS to search for weak CXE lines due to highly stripped CNFeMgNeSi
solar wind ions normally dominated by OVII and OVIII at 500-800 eV,
and detect OVI at 0.11 keV using the sensitivity of Chandra's HRC-I
camera to extremely soft x-rays. 3 identical visits are requested to
allow for solar wind variability.
NuSTAR
PI: Tomsick
Abstract: A goal of the NuSTAR mission is to study hard X-ray populations in the
Galaxy. While INTEGRAL has carried out a wide survey, uncovering many
new types of interesting and extreme sources (highly energetic PWNe,
new types of HMXBs, etc.), NuSTAR emphasizes going deeper into the
Galactic plane to look for hidden populations. NuSTAR recently found
its first new source, NuSTAR J163433-473838, during an observation of
the Norma spiral arm region. In addition to searching for known
sources in SIMBAD, CSC, etc., we are confident that it is a new source
as Chandra did not detect it during an observation in mid-2011. We are
looking for compact objects in regions with star formation to look for
faint HMXBs that are early in their evolutionary process or perhaps
magnetars or black holes that are expected to be associated with high
mass stars. We are requesting a Chandra observation to localize the
source in order to search for counterparts (e.g., near-IR) to
determine its nature.
PI: Henze
Abstract: What determines the life time of post-nova outburst supersoft X-ray
sources (SSSs)? A recent fast optical nova in M31 (ATels #4765,4768)
was detected surprisingly early (8 d post-discovery) in a Swift XRT
ToO. An XMM-Newton ToO was granted and unexpectedly revealed a
low-temperature SSS. Later, repeated Swift observations did not detect
the source after only 8 d of activity. This would not only indicate
the fastest SSS evolution of any known nova, it also places the object
well outside recently found correlations between nova parameters, as
only hot novae should evolve fast. However, due to its low-energy
response, Swift could not follow a more gradual decline in X-ray
luminosity and the target is now sun-constrained for XMM-Newton. We
strongly expect to be in agreement with current models and empirical
relations by detecting the nova with Chandra. A non-detection would
severely challenge our understanding of the connections between nova
observables.
PI: Madej
Abstract: In our Swift X-ray monitoring of M82 we found a new bright transient
which position does not correspond to any of the known sources in this
galaxy. We would like to investigate the nature of this transient
source.
PI: Vianello
Abstract: A GRB is highly beamed, while its afterglow is less so. In principle
this should allow to detect orphan afterglows , which has never
happened. The 1.5m MLS telescope of the CRTS discovered a peculiar
transient, which could be such an event. No GRB were detected at or
around that time. An obvious progenitor could be a low-mass star.
However, several co-added MLS images from before does not reveal the
source either, nor do all optical and X-ray surveys. Considering the
prototypical UV Ceti, this flare should have produced a brightening
above 7.5 mags, which would be extremely atypical (Kowalski et al.
2010). Observations with the Palomar 5m telescope (DBSP) and Palomar
1.5m showed no trace of the source (down to ~21st mag) 1 day after,
and 10 days later no photons were detected by Swift/XRT. This is
consistent with a typical afterglow with a power-law decay with
alpha=-1. Confirming the nature of this source would be extremely
valuable for our understanding of GRB afterglows.
PI: Orio
Abstract: Chandra gratings observations of novae in outburst have constrained
the models of accreting and hydrogen burning white dwarfs (novae and
the possible type Ia progenitors) and are allowing unprecedented
discoveries in the nova physics. The supersoft X-ray phase of novae
isthe only way to catch a glimpse of the white dwarf itself, when
hydrogen burning is still ongoing but only a thin atmosphere sits on
top of it. The proposer of this observations has assessed the
theoretical prediction that the white dwarf effective temperature is a
proxy for the white dwarf mass and this has opened many new
possibilities (see Orio 2012, aeXiv 1210.4331). Some novae also show
supersoft emission because of very strong emission lines in the
ejecta, revealing a whole new physics (see also Orio 2012).This nova
is exceptional, it was only one of three detected with the Fermi LAT,
and extremely high energy phenomena seem to happen in the ejecta
(possibly because of large amounts of circumstellar material).
off
PI: Tanvir
Abstract: Sw-J1644+57 was detected as a long-lived gamma-ray outburst in Mar
2011. Its unique H-E properties and location in the nucleus of a small
galaxy at z=0.35, suggested it was due to the tidal disruption of a
star by a 1-10 million Mo black-hole producing a relativistic jet. The
super-Eddington luminosity is understood by the jet pointing towards
us. Subsequent monitoring has shown the emission to decline roughly at
the expected -5/3 power-law for TDE fall-back, till a few weeks ago
when it abruptly "switched off". Our recent XMM data fixes the decline
to be a factor ~100 over only ~60d. Such a rapid shut-down of
accretion (~t^-25) seems implausible, so likely it represents the jet
launching mechanism turning off. We request a CXO observation, several
weeks after the XMM visit, to to establish whether the flux continues
to decline, or stabilises at a low level (eg. due to emission directly
from the accretion disk), thus shedding light on the poorly understood
process of jet production.
PI: Ness
Abstract: The nova Mon 2012 of Aug9 2012 (CBET 3202) has fortuitously been
observed with initial gamma ray emission >100MeV before it was
discovered in optical. Optical observations show similarities with the
ONe nova V382 Vel (1999) (ATel4310). Recent Swift observations yield a
surprisingly bright hard spectrum of a collisional plasma with 3keV
temperature and NH=3E22 (ATel4321), ~10 times the inferred
interstellar value. For these types of spectra we have shown to have
robust model techniques yielding abundances, velocity structure and
ionization state. The only nova grating spectrum of early hard
emission is of RS Oph, but without a giant companion, the origin in
Mon 2012 must be different. Constraining the nova ejecta with a
grating spectrum will illuminate on possible mechanisms for the
production of the initial >100 MeV gamma-rays that may in fact be
general to all high velocity ejection events.
PI: Troja
Abstract: The angular size of the GRB outflow is a key ingredient in determining
the total burst energy release and the true events rate. These
parameters are a crucial test for any progenitor and central engine
model. However, despite years of intense follow-up observations, the
degree of collimation of short GRBs still remains a missing piece of
information. Only a few short GRBs display a long-lived, and
relatively bright afterglow, detected in the X-ray, optical, and radio
bands. In these cases meaningful constraints on the jet opening angle
can be placed. We therefore propose to observe the afterglow of
GRB120804A with Chandra a few days after the explosion in order to
search for a jet-break, which is a clean diagnostic tool for
constraining the outflow geometry.
PI: Kaspi
Abstract: Magnetars are a class of neutron stars for which the majority of the
radiative output is believed to be powered by the decay of large
(~10E14-10E15 G) magnetic fields. On 2012 April 28, as seen in our
regular Swift monitoring observations, one well-known magnetar, 1E
2259+586, in SNR CTB109, entered a period of enhanced flux (ATel.
4080),and simultaneously suffered a timing anomaly. One proposed
mechanism to explain such outbursts is particle outflow (Thompson et
al. 2000) where large amounts of plasma are advected from the magnetar
at relativistic speeds. This suggests the possibility of a transient
outflow that could result in a jet-like or nebular X-ray structure. A
detection of a transient, small-scale X-ray nebula would be strong
evidence in favor of this model.
PI: Campana
Abstract: GRB120624B was detected by Swift and Fermi-LAT at very high energies,
but was Moon constrained for Swift follow-up. It is an extremely
bright burst, placing it in the brightest 1% of Swift and Fermi
bursts, only a factor of 2 fainter than the naked-eye GRB080319B. The
lightcurve shows much sub-structure, with hints of periodic behaviour.
A late 10ks Swift XRT observation located an X-ray afterglow candidate
at F_X~8e-14 ergs/s/cm^2. Such a faint X-ray afterglow is very
unusual. Bright bursts such as this one would typically be much
brighter at these times, by factor of ~10 (e.g. Gehrels et al. 2008).
Two deep NIR observations taken with VLT/HAWKI located a candidate,
but it is unusually faint too, and we cannot rule out an unrelated
source. This NIR source is not coincident with the X-ray source. Given
the unique nature of GRB120624B which appears unlike any previously
observed Swift burst, and the significant interest in tracking rare
Fermi-LAT bursts, we request a rapid Chandra ToO.
4088
PI: Mezcua
Abstract: We have recently detected compact radio emission from the ULX N4088-X1
using the EVN at 1.6 GHz consistent with steady jets from a black
hole. A series of Swift observations obtained around the same time
found the spectrum to be very hard, consistent with the low/hard state
when steady jets are expected. The radio and X-ray luminosities are
consistent with a black hole mass of ~10,000 Msun, however to
accurately measure the mass using the fundamental plane of accreting
black holes we need observations at 5 GHz. To this end we have been
awarded additional 5 GHz EVN observations in early June, and we
request a simultaneous Chandra DDT observation to accurately measure
the mass and confirm the association between the X-ray and radio
emission (for which a sub-arcsecond X-ray position is needed). If
confirmed, this would be the first detection of steady jets from an
intermediate mass black hole (IMBH), and would provide the first
accurate mass measurement of an IMBH.
PI: Neilsen
Abstract: The black hole candidate 4U 1630-47 recently entered an extremely
bright, active state in its outburst, with X-ray flux varying by a
factor of 4 on timescales of 1 day (mean flux ~0.3 Crab) and strong
hard X-ray emission (as seen by MAXI, Swift/BAT). Our recent
HETG/Suzaku observations of the source in a soft, steady state at 50%
lower flux revealed deep absorption lines from an extremely massive
disk wind. The new active state represents an excellent opportunity to
study how such massive winds respond to strong X-ray variability and
state changes, which have never been probed in 4U 1630-47. Our
proposed 20 ks CC-mode observation will reveal any long- and
short-term modulation in the massive disk wind, while additionally
providing simultaneous probes of any rapid X-ray variability and
changes in the X-ray continuum.
wind
PI: Soleri
Abstract: Miller et al. (2006, Nat., 441, 953) detected absorptions lines in the
Chandra spectra of the black hole GRO J1655-40 in the soft state,
associated with a disc wind. Ponti et al. (2012, MNRAS, 422, L11)
showed that disc winds are common among black holes in the soft state
(but see Neilsen & Homan 2012, ApJ, 750, 27); these winds are more
easily detected in nearly edge-on sources. Swift J1753.5-0127 is a
black hole candidate which has been active since May 2005 and it is
now entering the soft state (Atel #4056). From a fit to a broad Fe
line, Hiemstra et al. (2009, MNRAS, 394, 2080) found that the system's
inclination is high, although no dips or eclipses were observed. We
ask for a 20 ks Chandra observation to detect signatures of a disc
wind, set constraints on the driving mechanisms (which are still
unclear) and estimate the mass loss in the wind. If we also detect the
broad Fe line we can compare its properties to those in the hard
state.
PI: Drake
Abstract: Nova LMC 2012 is the first X-ray bright nova easily accessible to
Chandra gratings to have occurred in Swift Era. Unlike the highly
uncertain distances of novae in the Galaxy, the LMC is at known
distance and nova luminosities can be precisely measured.
Spectroscopic evidence and the fast evolution of the event suggests it
might be a recurrent nova. High resolution X-ray spectra will allow
diagnosis of the radiatively-driven outflow through line profiles, and
will provide a chemical composition snapshot of the supersoft source
envelope. Existing grating observations of novae have shown a diverse
array of spectral features, but recently a pattern has emerged in
which emission lines are stronger for smaller inclination angles. A
Chandra LETG spectrum will provide key insights into the emission
geometry and will help diagnose the processes underlying the
radiatively-driven outflow in what will be a close to Eddington
Luminosity source.
PI: Miller
Abstract: MAXI J1305-704 is a new X-ray transient, which has come up to a flux
level of 0.07 Crab (see ATEL 4044) and appears to be in a fairly soft
state. Dips have been observed in the X-ray flux, indicating a high
inclination, and possibly also a very short orbital period. This
represents an excellent chance to study the disk atmosphere in this
source, and connections to disk winds. Importantly, the line of sight
column density forthis source is low (1-2 E+21) and will enable
sensitive spectroscopy across the full HETGS band. A 30 ksec
observation of MAXI J1305-704 will yield approximately 1 million
photons in the MEG and HEG, at current flux levels.
supernova
PI: Corsi
Abstract: PTF 11qcj is a Ibn supernova (SN) discovered by PTF. Its spectra show
He emission lines, related to the interaction with a He-rich dense
shell. Only 4 SNe like this are known, the most famous is SN 2006jc.
11qcj is the only known case of a radio-loud Ibn SN. The Chandra X-ray
light curve of 2006jc supported the He-shell scenario, showing a flux
increase of a factor of 5 in the first 4 months after discovery,
different from the typical power-law decay of X-ray SNe interacting
with a circum-stellar wind. The two Chandra observations of 11qcj
reveal an X-ray luminosity 5x that of 2006jc (at a similar epoch).
Based on the template X-ray behavior of 2006jc, and on the radio
observations we collected so far for 11qcj (the radio emission seems
to track the X-ray behavior), we expect that 11qcj X-ray light curve
is now decreasing. We ask to re-observe 11qcj with Chandra before it
becomes too faint, so as to measure the X-ray light curve FWHM and
constrain the thickness of the dense shell.
PI: Ray
Abstract: We request a Chandra DDT observation of this IIP SN for 60 ks. In our
Chandra observation of 2012Jan10 (39.45 ks exposure, ObsID 13791) we
have detected the SN with 135 counts (0.3-3 keV, background
subtracted) in ACIS-S. A fixed-abs APEC model gives a good fit (kT=
1.6 +- 0.1 KeV and Flux (0.5-2 keV) = 8.8e-15 cgs, with excess
emission at 1.33 keV. The NEI model with free abundance of Mg XI
forbidden line at 1.334 keV can explain the line for a 3.69+/-1.37
fold overabundance of Mg (3 sigma). Both thermal & non thermal Inverse
Compton models can be conclusively ruled out. The line contains 21
counts. As the SN ages the forbidden line should decrease in strength
as gas comes into ionization equilibrium. Chandra observation will
confirm and model the existence of the Mg line and its evolution and
determine the SN ejecta structure. Stacked exposures can detect
further element lines. We have observed it with GMRT (ATel 3899).
PI: Wheatley
Abstract: The recent discovery that the super-Earth exoplanet 55 Cnc e transits
its 6th mag star provides the exciting opportunity to study the upper
atmosphere of a super-Earth for the first time. Our team has secured
HST DDT with the aim of searching for hydrogen escaping the planet (by
measuring absorption in Ly-alpha through two transits). The planet
density suggests that it may be composed largely of water, in which
case hydrogen evaporation may be expected from a photo-disassociating
super-critical ocean. We propose Chandra observations to measure the
X-ray flux of the host star at the time of both HST observations (on
Mar 7 and Apr 5). Exoplanet evaporation is thought to be driven by
X-ray irradiation, and combined X-ray/UV measurements are required to
measure the mass loss rate and determine the evaporation efficiency.
By measuring X-ray irradiation and the resulting evaporation through
two transits we can begin to study the response of a super-Earth
atmosphere to varying irradiation.
PI: Wheatley
Abstract: The recent discovery that the super-Earth exoplanet 55 Cnc e transits
its 6th mag star provides the exciting opportunity to study the upper
atmosphere of a super-Earth for the first time. Our team has secured
HST DDT with the aim of searching for hydrogen escaping the planet (by
measuring absorption in Ly-alpha through two transits). The planet
density suggests that it may be composed largely of water, in which
case hydrogen evaporation may be expected from a photo-disassociating
super-critical ocean. We propose Chandra observations to measure the
X-ray flux of the host star at the time of both HST observations (on
Mar 7 and Apr 5). Exoplanet evaporation is thought to be driven by
X-ray irradiation, and combined X-ray/UV measurements are required to
measure the mass loss rate and determine the evaporation efficiency.
By measuring X-ray irradiation and the resulting evaporation through
two transits we can begin to study the response of a super-Earth
atmosphere to varying irradiation.
supernova
PI: Corsi
Abstract: PTF 11qcj is a Ic supernova (SN) discovered by PTF. Its spectra show
He emission lines, related to the interaction with a He-rich dense
shell. Only 4 SNe like this (called type Ibn SNe), are known. The
prototype is the famous SN 2006jc. The exceptional thing about 11qcj
is that it is radio loud: only this one case of a radio-loud Ibn SN is
know. The Chandra X-ray light curve of 2006jc supported the He-shell
scenario, showing a flux increase of a factor of 5 in the first 4
months after discovery, different from the typical power-law decay of
X-ray SNe interacting with a circum-stellar wind. The Chandra
observation of 11qcj at about 80d since discovery, reveals an X-ray
luminosity 5x that of 2006jc (at a similar epoch). Aim of this
proposal is to track the evolution of 11qcj X-ray light curve, so as
to determine its peak flux and timescale, that are crucial for the
broad-band modeling (currently, we are carrying out an extensive
follow-up campaign in radio, optical, and infrared).
interacting with an He shell?
PI: Corsi
Abstract: PTF 11qcj is a Ic supernova (SN) discovered by PTF on 2011 Oct 23. Its
spectrum on day 34 shows He I emission lines which are very rare,
suggesting this a Ibn: a Ic SN interacting with a He-rich cold dense
shell (CDS). Only 4 Ibn SNe are known, the best studied prototype is
the famous SN 2006jc. The Chandra X-ray light curve of 2006jc
supported the CDS scenario, showing a flux increase of a factor of 5
in 4 months, very different from the power-law decay of X-ray SNe
interacting with a circum-stellar wind material (CSM). However, SN
2006jc was undetected in radio. PTF 11qcj may represent the first
discovery of a radio luminous Ibn: our EVLA observations at 40 d
reveal it is 100x more luminous than 2006jc in radio. This suggests
strong CSM interaction which, based on 2006jc, makes a detection with
Chandra likely. We thus request a Chandra observation: measuring the
X-ray luminosity of this event will allow us to constrain the density
of the CDS and confirm the Ibn nature of 11qcj.
PI: Hodges-Kluck
Abstract: A 08/2011 XMM observation of NGC 891 shows a bright (L_X ~ 2E40 erg/s;
F_X ~ 1E-12 erg/s/cm^2) new ULX near the disk. It is absent in
archival X-ray observations. Variability in Swift monitoring and the
absence of bright optical or radio counterparts rule out a SN. As a
bright ULX that recently "turned on" and whose spectrum indicates a
hot (kT ~ 1 keV) disk, the source may be an extreme example of
super-Eddington (5-50 L_Edd) accretion. Deep archival HST images
reveal a potential counterpart--a star cluster--within the 2" X-ray
error circle, but it is only 0.5" across. A better position is a
prerequisite for proposing deep spectroscopic follow-up, and the lack
of radio or optical counterparts in follow-up observations makes CXO
the only option. We expect an ACIS-S count rate of 0.07-0.2 cts/s, and
request 2 ks of DDT time to obtain 150-400 cts, thereby sampling the
PSF extremely well. Although a snapshot is susceptible to flaring, the
ULX is extremely bright.
magnetar laboratory
PI: Israel
Abstract: CXOUJ1647 is a transient magnetar which is currently in outburst
(September 2011). The previous one occurred in 2006. Preliminary
analysis of the timing and spectral parameters of the new outburst
suggest a different behaviour with respect to the 2006 event. The main
aims of the DDT request are: the detection of Pdot variations and
therefore of variations of the B-field topology during the 2
outbursts, and monitoring both the spectral and timing evolution in
order to compare them with those of 2006. In particular, the way the
parameters of the two events evolve will allow us to answer to the
following questions: Are all magnetar outbursts originated by large
displacements and/or cracks of the neutron star surface? Are the hot
spots originated by the outburst always occurring on the same places ?
We note that Chandra is currently the only mission able to point to
the source and to achieve a phase accuracy large enough for keeping
the coherency until the next visibility window.
PI: Hughes
Abstract: No SN Ia has been detected in the X-ray band during outburst. The most
careful limits have been set using a 20 ks Chandra observation of SN
2002bo in NGC 3190 (22 Mpc), which was observed 9.3 days after
explosion (Hughes et al. 2007), resulting in limits on the
circumstellar medium (CSM) of w = \dot M/ v_w < 1.2E15 g/cm, assuming
a wind density profile \rho_w = \dot M/(4\pi v_w r^2). This limit is
comparable to the limits set by the nondetection of H\alpha flux from
SN 1994D and SN 2001el, although they are less constraining than
limits set in the radio (Panagia et al. 2006). X-ray constraints are
based on direct calculation of the expected emission using
well-understood physics (i.e., bremsstrahlung emission,
Comptonization), while radio limits are subject to large systematic
uncertainties because the efficiency for generating synchrotron
radiation in the shocked wind and ejecta is not known. We will work
with Nikolai Chugai to model and intepret the results.
accreting millisecond pulsar IGR J17498-2921
PI: Di Salvo
Abstract: Papitto et al. (2011, ATel #3556) reported the discovery of a coherent
pulsed signal from the hard X-ray transient IGR J17498-2921 (Gibaud et
al. 2011, ATel #3551) at a frequency of 401 Hz, very similar to the
spin frequency of the first discovered Accreting Millisecond Pulsar
(AMSP) SAX J1808.4-3658. Taking advantage from the reported position
of the source (ATels #3558, #3559) we propose to observe this source
with Chandra/HETG in order to perform X-ray spectroscopy of the X-ray
spectrum of this interesting source and to get invaluable information
on the innermost emitting region. The PCA spectrum shows evidence of a
strong and broad iron emission line at 6.4 keV (sigma = 0.8 keV).
Chandra will be able to confirm that the line is produced at the inner
accretion disc. In this case, fitting with self-consistent reflection
models will give important information on the position of the
magnetospheric radius and on the neutron star magnetic field.
accreting millisecond pulsar IGR J17498-2921
PI: Di Salvo
Abstract: Papitto et al. (2011, ATel #3556) reported the discovery of a coherent
pulsed signal from the hard X-ray transient IGR J17498-2921 (Gibaud et
al. 2011, ATel #3551) at a frequency of 401 Hz, very similar to the
spin frequency of the first discovered Accreting Millisecond Pulsar
(AMSP) SAX J1808.4-3658. Taking advantage from the reported position
of the source (ATels #3558, #3559) we propose to observe this source
with Chandra/HETG in order to perform X-ray spectroscopy of the X-ray
spectrum of this interesting source and to get invaluable information
on the innermost emitting region. The PCA spectrum shows evidence of a
strong and broad iron emission line at 6.4 keV (sigma = 0.8 keV).
Chandra will be able to confirm that the line is produced at the inner
accretion disc. In this case, fitting with self-consistent reflection
models will give important information on the position of the
magnetospheric radius and on the neutron star magnetic field.
J1834-087?
PI: Kargaltsev
Abstract: J1834.9-0846 triggered the Swift/BAT and the Fermi/GBM on August 7,
2011. Although an SGR-like event was detected in both cases, a spin
period has not yet been found. Our ToO with RXTE will take place on
August 9. We observed the field with Chandra (Misanovic et al. 2010),
searching for a counterpart to an unidentified TeV source HESS
J1834-087 inside SNR W41. We found a point source, CXOU
J183434.9-084443, and offset extended emission. We re-examined these
Chandra (and archival XMM) data and found no point source at the XRT
position of J1834.9-0846, which, however, falls within the extended
structure seen in the Chandra and XMM images. We request 15ks with
ACIS-S to measure the spectrum of the new source, look for possible
compact PWN and pulsations, and perform phase-resolved spectroscopy
and energy-resolved timing. The Chandra data will be jointly analyzed
with the existing HESS and Fermi data. We will use 1/8 subarray to
probe periods as short as 0.4 s.
PI: Levan
Abstract: We recently observed GRB110709B under our c12 program. This burst was
both very dark (betaOX < -0.4), and unusual in triggering Swift/BAT
twice (separated by ~15 mins). This could indicate a high-z GRB, a
gravitationally lensed burst, or of (another) novel mechanism for GRB
production. Our CXO imaging showed two objects within or close to the
XRT error circle: the 1st (1.2" from XRT centroid) coincides with a
brightening radio source, presumed to be the GRB afterglow; the 2nd
lies at 2.7", and has near identical brightness. The second object may
also be associated with an optical source (which shows weak archival
evidence for variability), but the X/O offset is surprisingly large
(~0.8"). A second CXO visit to search for variability would greatly
clarify this situation. Is the 2nd source simply a chance foreground
object? Does the 1st source behave like a conventional X-ray
afterglow? The major followup devoted to this most unusual GRB makes a
strong case for another visit.
PI: Kouveliotou
Abstract: Swift J1822.3-1606 was detected with the BAT during a ground search of
the data; it also triggered the Fermi/GBM when it emitted a series of
~5 Soft Gamma Repeater like X-ray bursts, each one lasting ~ 5 ms. We
observed the persistent emission of the source with the RXTE/PCA and
confirmed the pulse period of 8.4377585 s. Moreover, we determined a
very high pulsed fraction of the signal of at least 41%. This pulsed
fraction is highly unlikely for an SGR. The source could well be
another Swift J1626.6-5156 (most likely a Be-X-ray binary) or
alternatively, another rotation powered pulsar like PSR
J1846−0258, which was detected to emit SGR-like bursts. The
latter option was the first of its kind linking high B-field pulsars
to SGRs. We are seeking CXO/HRC observations of Swift J1822.3-1606 to
determine the most accurate source location, which will enable us to
identify the source counterpart in this congested region. The current
positional accuracy with Swift XRT is 3.5".
Black Hole?
PI: Cenko
Abstract: The recent discovery of the transient source Swift J1644 has revealed
a potential new class of high-energy outbursts. Like long-duration
gamma-ray bursts, these sources exhibit a prompt, dramatic energy
release which drives a relativistic outflow. However, the central
engine powering these events is the massive black hole at the center
of a normal galaxy. More recently, Swift has discovered another
high-energy transient, Swift J2058, with broadly similar high-energy
properties. Within the XRT localization (1.7" radius), we have
identified the likely optical counterpart as an absorption line galaxy
at z=1.185. At this redshift, the X-ray luminosity (4e47 erg/s) and
X-ray-to-optical flux ratio (12,000:1) are essentially identical to
that observed from Swift J1644. Here we request HRC-I observations of
Swift J2058 to a) provide precise astrometry (to establish or refute a
nuclear origin), and b) measure the variability time scale (to
constrain the mass of the accreting source).
PI: Sivakoff
Abstract: On May 16, MAXI detected an X-ray burst from the globular cluster M15.
Today (5/18) Swift confirmed that either the edge-on ADC source AC 211
or the ultracompact (22-min period) M15 X-2 is flaring (L~1.3E37). It
is unlikely that AC 211 is responsible as one does not expect to see
bursts from ADC sources. The standard paradigm for ultracompact XRBs
like M15 X-2 is that they "should" show stable mass transfer. The few
Chandra observations of M15 X-2 have not showed significant
variations, but today's measured luminosity was 10 times that
typically measured. The 17-minute ultracompact XRB in NGC 1851 has
shown variability by factors of >10 (Maccarone et al. 2010, MNRAS,
406, 2087), a behavior that remains unexplained. Determining that a
second ultracompact exhibits large variations would significantly
challenge the standard paradigm for accretion in ultracompact XRBs.
PI: Miller
Abstract: We have recently discovered an extended source with dual ring-like
structure in a shallow Swift image in the Galactic Plane. The
structure is strongly suggestive of a pulsar wind nebula. A known B
star is plausibly associated with the extended source, which means
that the neutron star could be in a binary, and that we could capture
an image of a very young X-ray binary that will eventually become a
double neutron-star system. A short Chandra exposure of just 5 ksec
will be sufficient to confirm the structures suggested by the Swift
image, to obtain a spectrum with approximately 4000 photons, and to
enable multi-wavelength follow-up observations in the near future.
Candidate
PI: Gezari
Abstract: We propose for a DDT observation of a candidate tidal disruption event
(TDE) discovered in coordinated UV GALEX and optical Pan-STARRS1 (PS1)
observations. The long-lasting blue color (NUV-r < -1.2) during the
slow decay of the flare over 10 months of GALEX+PS1 monitoring is
unlike any known supernova behavior, and is consistent with the hot
blackbody emission and t^(-5/3) luminosity decay of a TDE. X-ray
observations are critical for determining the broadband SED of the
flare, which is theoretically expected to peak in the soft X-rays.
This flare would have satisfied our Chandra Cycle 11 TOO criteria when
it was discovered in 2010 June, however the first optical spectrum
taken on 2010 June 16 detected an isolated broad emission line that
was misidentified as Mg II at z=0.96. A later spectrum taken on 2011
April 7 revealed absorption features from the host galaxy at z=0.170,
indicating that the broad feature was in fact He II, a high ionization
line associated with TDEs!
X-ray pulsar in the globular cluster Terzan 5
PI: Degenaar
Abstract: A new bright transiently accreting neutron star was discovered in
Terzan 5 in 2010 October. We obtained a Chandra DDT observation in
February, ~2 months after the end of the outburst, and found the
neutron star a factor ~4 hotter than measured in archival Chandra data
(Degenaar & Wijnands 2011a,b). This indicates that the crust was
severely heated during outburst and that it is possible to observe the
crust cooling curve of this source. However, our target likely cools
considerably faster than previous studied sources, because the short
(~2 months) outburst duration only heated the outer layers of the
neutron star crust (see webpage specified below), which loose the
deposited heat already within months. We request a Chandra DDT
observation to further monitor the cooling curve and put important new
constraints on the neutron star crust: the slope of the cooling curve
directly measures the heat flux in the outer crust, hence the amount
and distribution of heat sources.
PI: Guenther
Abstract: We have recently discovered variability in X-ray indicators of
accretion in the CTTS TW Hya. We seek to use this to understand the
physics of accretion in our upcoming HST observations. We have been
granted 10 HST orbits and 15 CRIRES pointings to monitor the C IV 155
nm doublet and the He I 1083 nm line in TW Hya, the closest CTTS, to
correlate i) the hot wind ii) the cool wind iii) the photometric
period iv) the accretion. In existing HETGS data of TW Hya we see
variability in emission lines from the accretion shock on the star.
However, the densities in Ne IX and O VII indicate that today's shock
models are incomplete. A hot wind is the most promising candidate for
this missing component. Our HST observations will characterize the
wind and we ask for 20 ks Chandra time with LETGS/ACIS simultaneous to
HST to determine the state of accretion. The high effective area of
LETGS/ACIS gives > 100 counts in the O VII and Ne IX triplets, so we
can measure the density and temperature.
PI: Torres
Abstract: We request 50 ks Chandra time to check for the existence of X-ray
pulsations from HESS J0632+057. The latter is associated with XMMU
J063259.3+054801 / Be star MWC 148 and has shown a recent increase in
X-ray activity, based on Swift-XRT monitoring (ATEL #3152). We have
used this and previous Swift observations (Falcone et al. 2010, ApJ
708, L52) to positively evaluate the Chandra visibility. HESS
J0632+057 was recently discovered (Aharonian et al. 2007, A&A, 469,
L1), and proposed to be a member of just a handle of such binaries
that emit in gamma-rays. Knowing about its composition is essential
for modeling (e.g., Mirabel 2006, Science 1759). Search for pulsations
from gamma-ray binaries with Chandra have provided the most stringent
upper limits yet (Rea et al. 2010, MNRAS 405, 2206), and its detection
would be a breakthrough for the understanding of these systems.
globular cluster Terzan 5
PI: Wijnands
Abstract: We have intensively studied the crust cooling of accreting neutron
stars. We have focused on systems with outbursts lasting years to
decades for which observing the crust cooling is most feasible.
However, as already suggested in Brown et al. 1998 (see the link given
in the TOO Trigger criteria section) crust cooling might also be
observable for systems which have a low quiescent temperature and very
bright but short (weeks/months) outbursts. A recent new transient in
Terzan 5 reached ~1E38 erg/s and its outburst lasted at most a few
months. Combined with its very low quiescent temperature (Degenaar &
Wijnands 2011) this source is an ideal target to test this and to
provide valuable input to any crust-cooling model. Adding this source
to our sample will also be very important to understand the observed
differences between sources and whether this is related to their
different outburst properties and further put constraints on the
properties (ie the crust) of accreting neutron stars.
PI: McClintock
Abstract: We are about to submit a paper to Science on the near-maximal spin
(a/M>0.97) of Cyg X-1 [1]. This premier result is largely based on two
DDT Chandra (plus RXTE) spectra obtained last July, two weeks after
Cyg X-1 entered its soft state on 7 July. For these observations, the
Compton component was relatively strong ("scattered fraction" f=34%),
well above the established limit of reliability for our spin method,
which is f=25% [1]. In mid-October, Cyg X-1 entered a "supersoft"
state [1], and we now propose to obtain one additional Chandra
observation (HETG; TE mode; 12 ks) in order to secure our result. We
expect to obtain a Compton-weak spectrum with f<25% (like our 1996
ASCA/RXTE spectrum with f=24%) [1]. To date, our group has measured
the spins of 9 black holes, and this result for Cyg X-1 is distinctly
our most important and exciting [2]. REFERENCES: [1]
https://www.cfa.harvard.edu/~lgou/cygx1/cygx1.html [2]
http://arxiv.org/abs/0909.0169 AND http://arxiv.org/abs/1004.3558
Anomalous X ray Pulsar XTE j1810-197
PI: Perna
Abstract: The goal of our analysis is to probe a possible long term (5 yr)
free-body precession of this neutron star for which we found several
indications based on a non-phase-connected timing analysis. Although
only 3 NS up to now have shown indication of precession, such evidence
strongly challenges our current understanding of the NS interior. The
standard picture of the outer core, in which superfluid neutrons
coexist with type II superconducting protons, requires revision. One
possibility is that protons are type I which would imply a significant
revision of our picture of the physical conditions in the NS core.
Another possibility is that the neutrons are normal in the outer core
which again affects our understanding of the physical state of NSs
core. The presence of long period modulation can shed light on the
physical properties of NS and thus help constraining its equation of
state
PI: Filippenko
Abstract: As part of the Lick Observatory Supernova Search (LOSS), we have
recently identified an unusual optical outburst from the nucleus
(within 0.05";, or 10 pc in projection) of the nearby (d ~ 50 Mpc)
spiral (S0/a) galaxy NGC 1589. Over a decade of photometric monitoring
with LOSS, together with archival spectroscopy from the CfA Redshift
Survey, suggest the galaxy does not harbor an active galactic nucleus.
Likewise, the bright observed X-ray emission and complex H-alpha
emission profile do not appear to resemble any known Type II
supernova. We therefore believe this transient source (dubbed
NGC1589-OT) represents the most viable candidate for a tidal
disruption flare (TDF) ever discovered in real time. Here we request a
10 ks Chandra/ACIS DD observation to accurately constrain the X-ray
spectral properties (power-law vs. thermal) and environment (n_H) of
this unique, fascinating source. In a separate proposal, we are also
requesting HST time to get a UV spectrum of it.
PI: Weisskopf
Abstract: Subsequent to the detection of a gamma ray flare in September, Chandra
has been used to monitor the structure and spectrum of the Crab
Nebula. This flare was first detected by AGILE (ATEL 2855)and had a
timescale of days. The event was also seen with the Fermi Satellite.
These S/C have also observed flaring at other times and with longer
timescales. The Sept. event has received international attention and
it appears that the flaring is not directly associated with the
pulsar, but with the nebular flux. The timescale indicates an emitting
region as small as 0.5-1.0 arcsec at two kpc. Chandra has shown that
there are many features of this scale in the nebula and that they are
constantly changing. It is essential that a viable baseline be
established in order to obtain useful information from future
observations triggered by another flare. We propose a series of
monitoring observations.
PI: Weisskopf
Abstract: Subsequent to the detection of a gamma ray flare in September, Chandra
has been used to monitor the structure and spectrum of the Crab
Nebula. This flare was first detected by AGILE (ATEL 2855)and had a
timescale of days. The event was also seen with the Fermi Satellite.
These S/C have also observed flaring at other times and with longer
timescales. The Sept. event has received international attention and
it appears that the flaring is not directly associated with the
pulsar, but with the nebular flux. The timescale indicates an emitting
region as small as 0.5-1.0 arcsec at two kpc. Chandra has shown that
there are many features of this scale in the nebula and that they are
constantly changing. It is essential that a viable baseline be
established in order to obtain useful information from future
observations triggered by another flare. We propose a series of
monitoring observations.
PI: Weisskopf
Abstract: Subsequent to the detection of a gamma ray flare in September, Chandra
has been used to monitor the structure and spectrum of the Crab
Nebula. This flare was first detected by AGILE (ATEL 2855)and had a
timescale of days. The event was also seen with the Fermi Satellite.
These S/C have also observed flaring at other times and with longer
timescales. The Sept. event has received international attention and
it appears that the flaring is not directly associated with the
pulsar, but with the nebular flux. The timescale indicates an emitting
region as small as 0.5-1.0 arcsec at two kpc. Chandra has shown that
there are many features of this scale in the nebula and that they are
constantly changing. It is essential that a viable baseline be
established in order to obtain useful information from future
observations triggered by another flare. We propose a series of
monitoring observations.
PI: Weisskopf
Abstract: Subsequent to the detection of a gamma ray flare in September, Chandra
has been used to monitor the structure and spectrum of the Crab
Nebula. This flare was first detected by AGILE (ATEL 2855)and had a
timescale of days. The event was also seen with the Fermi Satellite.
These S/C have also observed flaring at other times and with longer
timescales. The Sept. event has received international attention and
it appears that the flaring is not directly associated with the
pulsar, but with the nebular flux. The timescale indicates an emitting
region as small as 0.5-1.0 arcsec at two kpc. Chandra has shown that
there are many features of this scale in the nebula and that they are
constantly changing. It is essential that a viable baseline be
established in order to obtain useful information from future
observations triggered by another flare. We propose a series of
monitoring observations.
PI: Weisskopf
Abstract: Subsequent to the detection of a gamma ray flare in September, Chandra
has been used to monitor the structure and spectrum of the Crab
Nebula. This flare was first detected by AGILE (ATEL 2855)and had a
timescale of days. The event was also seen with the Fermi Satellite.
These S/C have also observed flaring at other times and with longer
timescales. The Sept. event has received international attention and
it appears that the flaring is not directly associated with the
pulsar, but with the nebular flux. The timescale indicates an emitting
region as small as 0.5-1.0 arcsec at two kpc. Chandra has shown that
there are many features of this scale in the nebula and that they are
constantly changing. It is essential that a viable baseline be
established in order to obtain useful information from future
observations triggered by another flare. We propose a series of
monitoring observations.
PI: Weisskopf
Abstract: Subsequent to the detection of a gamma ray flare in September, Chandra
has been used to monitor the structure and spectrum of the Crab
Nebula. This flare was first detected by AGILE (ATEL 2855)and had a
timescale of days. The event was also seen with the Fermi Satellite.
These S/C have also observed flaring at other times and with longer
timescales. The Sept. event has received international attention and
it appears that the flaring is not directly associated with the
pulsar, but with the nebular flux. The timescale indicates an emitting
region as small as 0.5-1.0 arcsec at two kpc. Chandra has shown that
there are many features of this scale in the nebula and that they are
constantly changing. It is essential that a viable baseline be
established in order to obtain useful information from future
observations triggered by another flare. We propose a series of
monitoring observations.
PI: Weisskopf
Abstract: Subsequent to the detection of a gamma ray flare in September, Chandra
has been used to monitor the structure and spectrum of the Crab
Nebula. This flare was first detected by AGILE (ATEL 2855)and had a
timescale of days. The event was also seen with the Fermi Satellite.
These S/C have also observed flaring at other times and with longer
timescales. The Sept. event has received international attention and
it appears that the flaring is not directly associated with the
pulsar, but with the nebular flux. The timescale indicates an emitting
region as small as 0.5-1.0 arcsec at two kpc. Chandra has shown that
there are many features of this scale in the nebula and that they are
constantly changing. It is essential that a viable baseline be
established in order to obtain useful information from future
observations triggered by another flare. We propose a series of
monitoring observations.
PI: Simpson
Abstract: We have recently discovered the most distant QSO, ULAS J1120+0641, at
z=7.08, smashing the previous record of z=6.44. This object was
discovered by surveying 2250deg^2 of UKIDSS and SDSS, extending the
technique used by high-z QSO surveys into the near-IR. Based on its
rest-frame UV luminosity, the QSO is powered by a black hole of mass
~1e9Msun just 760Myr after the Big Bang. The presence of such a
massive collapsed object when the Universe was so young is a serious
challenge to models of structure formation and places strong
constraints on the growth of supermassive black holes in the early
Universe. We propose a CXO observation of ULAS J1120+0641 to measure
its X-ray flux. This will immediately provide a more reliable estimate
of its bolometric luminosity and black hole mass, and is also
necessary for us to determine the feasibility of a deep XMM spectral
observation to measure the X-ray photon index and Eddington ratio, and
compare its X-ray properties with those of other QSOs.
PI: Liu
Abstract: The Kepler mission has proved powerful in understanding the accretion
disks around compact objects for its un-interrupted monitoring
capability with time resolutions of minutes. Previous Kepler
observations of symbiotics and Cataclysmic Variables have successfully
probed the structures of the accretion flows around white dwarfs. In
the third and final Kepler cycle, we will seek to probe the accretion
flows around more compact neutron stars and black holes with Kepler
light curves, a regime never been studied before. There are no
existing studies of low-mass X-ray binaries (LMXBs) in the Kepler
field; we select LMXB candidates from ROSAT all sky survey (RASS)
sources in the Kepler field based on hardness ratios, X-ray-to-optical
ratios, and source extent aided by visual inspection. Here we propose
short Chandra observations for this sample of 15 LMXB candidates to
determine their exact nature and optical counterparts.
PI: Liu
Abstract: The Kepler mission has proved powerful in understanding the accretion
disks around compact objects for its un-interrupted monitoring
capability with time resolutions of minutes. Previous Kepler
observations of symbiotics and Cataclysmic Variables have successfully
probed the structures of the accretion flows around white dwarfs. In
the third and final Kepler cycle, we will seek to probe the accretion
flows around more compact neutron stars and black holes with Kepler
light curves, a regime never been studied before. There are no
existing studies of low-mass X-ray binaries (LMXBs) in the Kepler
field; we select LMXB candidates from ROSAT all sky survey (RASS)
sources in the Kepler field based on hardness ratios, X-ray-to-optical
ratios, and source extent aided by visual inspection. Here we propose
short Chandra observations for this sample of 15 LMXB candidates to
determine their exact nature and optical counterparts.
PI: Liu
Abstract: The Kepler mission has proved powerful in understanding the accretion
disks around compact objects for its un-interrupted monitoring
capability with time resolutions of minutes. Previous Kepler
observations of symbiotics and Cataclysmic Variables have successfully
probed the structures of the accretion flows around white dwarfs. In
the third and final Kepler cycle, we will seek to probe the accretion
flows around more compact neutron stars and black holes with Kepler
light curves, a regime never been studied before. There are no
existing studies of low-mass X-ray binaries (LMXBs) in the Kepler
field; we select LMXB candidates from ROSAT all sky survey (RASS)
sources in the Kepler field based on hardness ratios, X-ray-to-optical
ratios, and source extent aided by visual inspection. Here we propose
short Chandra observations for this sample of 15 LMXB candidates to
determine their exact nature and optical counterparts.
PI: Liu
Abstract: The Kepler mission has proved powerful in understanding the accretion
disks around compact objects for its un-interrupted monitoring
capability with time resolutions of minutes. Previous Kepler
observations of symbiotics and Cataclysmic Variables have successfully
probed the structures of the accretion flows around white dwarfs. In
the third and final Kepler cycle, we will seek to probe the accretion
flows around more compact neutron stars and black holes with Kepler
light curves, a regime never been studied before. There are no
existing studies of low-mass X-ray binaries (LMXBs) in the Kepler
field; we select LMXB candidates from ROSAT all sky survey (RASS)
sources in the Kepler field based on hardness ratios, X-ray-to-optical
ratios, and source extent aided by visual inspection. Here we propose
short Chandra observations for this sample of 15 LMXB candidates to
determine their exact nature and optical counterparts.
PI: Liu
Abstract: The Kepler mission has proved powerful in understanding the accretion
disks around compact objects for its un-interrupted monitoring
capability with time resolutions of minutes. Previous Kepler
observations of symbiotics and Cataclysmic Variables have successfully
probed the structures of the accretion flows around white dwarfs. In
the third and final Kepler cycle, we will seek to probe the accretion
flows around more compact neutron stars and black holes with Kepler
light curves, a regime never been studied before. There are no
existing studies of low-mass X-ray binaries (LMXBs) in the Kepler
field; we select LMXB candidates from ROSAT all sky survey (RASS)
sources in the Kepler field based on hardness ratios, X-ray-to-optical
ratios, and source extent aided by visual inspection. Here we propose
short Chandra observations for this sample of 15 LMXB candidates to
determine their exact nature and optical counterparts.
PI: Liu
Abstract: The Kepler mission has proved powerful in understanding the accretion
disks around compact objects for its un-interrupted monitoring
capability with time resolutions of minutes. Previous Kepler
observations of symbiotics and Cataclysmic Variables have successfully
probed the structures of the accretion flows around white dwarfs. In
the third and final Kepler cycle, we will seek to probe the accretion
flows around more compact neutron stars and black holes with Kepler
light curves, a regime never been studied before. There are no
existing studies of low-mass X-ray binaries (LMXBs) in the Kepler
field; we select LMXB candidates from ROSAT all sky survey (RASS)
sources in the Kepler field based on hardness ratios, X-ray-to-optical
ratios, and source extent aided by visual inspection. Here we propose
short Chandra observations for this sample of 15 LMXB candidates to
determine their exact nature and optical counterparts.
PI: Liu
Abstract: The Kepler mission has proved powerful in understanding the accretion
disks around compact objects for its un-interrupted monitoring
capability with time resolutions of minutes. Previous Kepler
observations of symbiotics and Cataclysmic Variables have successfully
probed the structures of the accretion flows around white dwarfs. In
the third and final Kepler cycle, we will seek to probe the accretion
flows around more compact neutron stars and black holes with Kepler
light curves, a regime never been studied before. There are no
existing studies of low-mass X-ray binaries (LMXBs) in the Kepler
field; we select LMXB candidates from ROSAT all sky survey (RASS)
sources in the Kepler field based on hardness ratios, X-ray-to-optical
ratios, and source extent aided by visual inspection. Here we propose
short Chandra observations for this sample of 15 LMXB candidates to
determine their exact nature and optical counterparts.
PI: Liu
Abstract: The Kepler mission has proved powerful in understanding the accretion
disks around compact objects for its un-interrupted monitoring
capability with time resolutions of minutes. Previous Kepler
observations of symbiotics and Cataclysmic Variables have successfully
probed the structures of the accretion flows around white dwarfs. In
the third and final Kepler cycle, we will seek to probe the accretion
flows around more compact neutron stars and black holes with Kepler
light curves, a regime never been studied before. There are no
existing studies of low-mass X-ray binaries (LMXBs) in the Kepler
field; we select LMXB candidates from ROSAT all sky survey (RASS)
sources in the Kepler field based on hardness ratios, X-ray-to-optical
ratios, and source extent aided by visual inspection. Here we propose
short Chandra observations for this sample of 15 LMXB candidates to
determine their exact nature and optical counterparts.
PI: Liu
Abstract: The Kepler mission has proved powerful in understanding the accretion
disks around compact objects for its un-interrupted monitoring
capability with time resolutions of minutes. Previous Kepler
observations of symbiotics and Cataclysmic Variables have successfully
probed the structures of the accretion flows around white dwarfs. In
the third and final Kepler cycle, we will seek to probe the accretion
flows around more compact neutron stars and black holes with Kepler
light curves, a regime never been studied before. There are no
existing studies of low-mass X-ray binaries (LMXBs) in the Kepler
field; we select LMXB candidates from ROSAT all sky survey (RASS)
sources in the Kepler field based on hardness ratios, X-ray-to-optical
ratios, and source extent aided by visual inspection. Here we propose
short Chandra observations for this sample of 15 LMXB candidates to
determine their exact nature and optical counterparts.
5
PI: Bhattacharyya
Abstract: The observation of the unique neutron star low-mass X-ray binary
(LMXB) EXO 1745-248 during its current outburst holds the promise to
address several important scientific problems. These are (1) use of
narrow absorption and emission features to probe the ionized and
neutral components above the accretion disk of LMXBs (Jimenez-Garate
et al. 2003); (2) measurement of the disk inner edge radius from the
broad relativistic iron line, and hence to probe the strong gravity
regime and the neutron star parameters (Bhattacharyya and Strohmayer
2007; Cackett et al. 2008); and (3) measurement of the neutron star
radius-to-mass ratio from narrow surface atomic spectral lines during
thermonuclear X-ray bursts. An observation with Chandra is required
because (1) it has unique high-resolution spectral capability, and (2)
this satellite will be able to observe the source throughout the
outburst (which XMM-Newton and Suzaku cannot do because of Sun angle
constraints).
the Crab
PI: Weisskopf
Abstract: Both the AGILE and Fermi satellites detected significant variation in
the emission above 100 MeV from the Crab Nebula. Moreover, there
appears to be a 1100 day counter variation in the x-ray flux from the
nebula seen with a number of satellites (figure sent separately). The
source of the enhancement seems to be associated with the brightening
of a knot appearing in the vicinity of the pulsar as seen by our team
using both Chandra and subsequently HST. Only Chandra has the imaging
spectroscopic capability to study such features, which we would then
correlate with the gamma-ray flux.
the Crab
PI: Weisskopf
Abstract: Both the AGILE and Fermi satellites detected significant variation in
the emission above 100 MeV from the Crab Nebula. Moreover, there
appears to be a 1100 day counter variation in the x-ray flux from the
nebula seen with a number of satellites (figure sent separately). The
source of the enhancement seems to be associated with the brightening
of a knot appearing in the vicinity of the pulsar as seen by our team
using both Chandra and subsequently HST. Only Chandra has the imaging
spectroscopic capability to study such features, which we would then
correlate with the gamma-ray flux.
the Crab
PI: Weisskopf
Abstract: Both the AGILE and Fermi satellites detected significant variation in
the emission above 100 MeV from the Crab Nebula. Moreover, there
appears to be a 1100 day counter variation in the x-ray flux from the
nebula seen with a number of satellites (figure sent separately). The
source of the enhancement seems to be associated with the brightening
of a knot appearing in the vicinity of the pulsar as seen by our team
using both Chandra and subsequently HST. Only Chandra has the imaging
spectroscopic capability to study such features, which we would then
correlate with the gamma-ray flux.
the Crab
PI: Weisskopf
Abstract: Both the AGILE and Fermi satellites detected significant variation in
the emission above 100 MeV from the Crab Nebula. Moreover, there
appears to be a 1100 day counter variation in the x-ray flux from the
nebula seen with a number of satellites (figure sent separately). The
source of the enhancement seems to be associated with the brightening
of a knot appearing in the vicinity of the pulsar as seen by our team
using both Chandra and subsequently HST. Only Chandra has the imaging
spectroscopic capability to study such features, which we would then
correlate with the gamma-ray flux.
the Crab
PI: Weisskopf
Abstract: Both the AGILE and Fermi satellites detected significant variation in
the emission above 100 MeV from the Crab Nebula. Moreover, there
appears to be a 1100 day counter variation in the x-ray flux from the
nebula seen with a number of satellites (figure sent separately). The
source of the enhancement seems to be associated with the brightening
of a knot appearing in the vicinity of the pulsar as seen by our team
using both Chandra and subsequently HST. Only Chandra has the imaging
spectroscopic capability to study such features, which we would then
correlate with the gamma-ray flux.
Anomalous X ray Pulsar XTE j1810-197
PI: Bernardini
Abstract: The goal of our analysis is to probe a possible long term (5 yr)
free-body precession of this neutron star for which we found several
indications based on a non-phase-connected timing analysis. Although
only 3 NS up to now have shown indication of precession, such evidence
strongly challenges our current understanding of the NS interior. The
standard picture of the outer core, in which superfluid neutrons
coexist with type II superconducting protons, requires revision. One
possibility is that protons are type I which would imply a significant
revision of our picture of the physical conditions in the NS core.
Another possibility is that the neutrons are normal in the outer core
which again affects our understanding of the physical state of NSs
core. The presence of long period modulation can shed light on the
physical properties of NS and thus help constraining its equation of
state
PI: Rea
Abstract: On 2009 June 5 two SGR-like bursts were emitted by SGR 0418+5729
(Esposito et al. 2010, MNRAS, 405, 1787). Although this SGR showed all
the characteristics of SGRs' outbursts, a phase-coherent timing
solution over the first ∼500 d yielded no evidence for any pdot,
implying a 3σ u.l. on the B-field of <7.5 10^{12} G (Rea et al.
2010, Science in press). This is the lowest magnetic field ever
observed for a magnetar, and the first lower than the electron
critical B (~4x10^{13} G). Such a low a external dipolar B-field might
hide an internal high-B of ~10^{14} G, needed to trigger the
magnetar-like activity. The external B can be at most ~80 times the
dipolar surface B. We ask for an ACIS-S observation of 30ks in
December 2010 to keep the phase-coherence of our timing solution, and
hopefully have a final detection of the B-field of this low magnetic
field magnetar. If the B will end up to be < 10^12 Gauss, this would
pose serious difficulties on the magnetar model.