@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @ @ @ MTA Monitoring Report 5/19/00 - 5/25/00 @ @ @ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ *********** Lost Data Update ************** Dan Rehner told that they could not recover much from the damaged disks. It means that we lost all processed data between 5/2 and 5/7 from /data/mta/www directory. Data before 5/1 are supposed to be backed up on tapes, but so far they are not restored yet. The data are expected to be reloaded sometime next week. Although we are planning to re-process the data, no schedule is set yet. MTA Task Missing? Location ------------------------------------------------------------ MTA monitoring 5/2-5/7 /mta/www/mp_reports MTA CTI several holes. /data/mta/www/mta_temp/mta_cti MTA focal temp recovered /data/mta/www/mta_temp/mta_fp MTA trending no damages /data/mta/www/mta_temp/mta_trends MTA states no damages /data/mta/www/mta_temp/mta_states All /mta_trend/... are temporary directories. ************ CTI trend ************* No major changes are observed. Software Note: A new plot is added on the page: a detrended acis-I Mn Ka. The basic idea is to use the "events rejected for having PHA over 3750" on S3 as a measure of the background. Then divide the measure CTI by a normalized form of this result to get a detrended CTI. For a reference, please see: http://space.mit.edu/%7Ecgrant/cti/index.html Since this plot is not fully automated, it won't up-dated daily yet. Please use it with a caution. ************** MTA Problem Tracking ***************** No new problem was reported. The following msids keep coming. AOVAMPWR, AOFUNLST, AWD1TQI, AWD4TQI, SEHSE400, 2CE01ATM, 2CE00ARM, AWD6TQI ******** Trending *********** No new trends. Some of new trends reported in the last several weeks are much more clear now. Regarding failures of coarse sun sensors on Rocsat, please read: http://asc.harvard.edu/mta/trend_alerts.html#CSS ************* Telemetry *********** On 5/23, HRC housekeeping data (PRBSCR,C24PALV,C05PALV,C15PALV,IMINATM, SMTRATM, and SPHVATM) triggered a few red warnings. This is first time in a while that they triggered the warnings. It appears, however, usual software glitches. On 5/24, HRC electronics settings were changed (IMHBLV, IMHVLV, RSRFALV, SPHBLV, SPHVLV). This is due to change from Hrc-S to Hrc-I (the change happened on 2000:144:02:39). On 5/25, TFTE's HTFTEGRD9 was flared up in red. Rino Giordano (rgiordano@head-cfa) reported: A long duration negative pitch (-166) observation on day 137 cause many areas of the observatory to decrease in temperature. This tail sun attitude is our coldest thermal orientation. Two telescope passive analog temperatures did caution at the lower set point of 48 F. (4RT597T & 4RT598T). They are located on the Aft TFTE cylinder -Z side. The limits were change to 46 F for both. During the day 137 observation the OBA and Periscope gradients had the following changes. OBA DIAMETRICAL 2.5 to 0.5 OBA AXIAL -1.0 to 0.5 PERISCOPE AXIAL 0.75 to 0.85 Telescope power increased from average 175 to 200 on day 137 3 thermal issues: * Day 137 observation (obsid 637) had large pitch attitude of 166 degrees for over a day. (Tail to sun) He saw periscope and OBA temperatures and gradients that were larger than nominal but still in spec. Aspect scientists notified. * Ultra-Stable-Oscillator (USO) had much larger temp variations than normal last week (controlled oven temp). He was going to look into the requirements and look more closely at this temp over time. Due to the coarse calibration curve, 1 ount=4.5 deg F, it is toggling a lot. It has changed by ~ 1 count since day 1999:250. Bill Davis sees ~20 usec excursion in clock correlation residuals. These residuals have moved around by up to ~15 usec in the past, however. * He saw some offsets in equilibrium temp values for some HRMA temps over the last safe-mode event. They are still well within spec, but he will examine why there were such offsets. *********** ACIS Focal Temperature ******** Acis focal plane temperature peaked three times: Day (DOY) Temp (C) Width (DAY) 138.53 -112.4 C 0.16 114.16 -111.9 C 0.20 143.82 -112.6 C 0.19 where the width is defined by a difference between a start and an end points of the peak, assuming the baseline is at -119 C. It is not a fwhm nor a standard deviation. Bev LaMarr (fergason@space.mit.edu) reported an event for the last week: I'm updating the obsid list and noticed that last Wednesday (day 138, 18May2000) for the CTI run going into the belts (obsid 62053 on the S-array) the focal plane temperature was low (-119.22C) at the beginning of the run. I checked the science run immediately preceding it (obsid 637 of "RHO_OPH_A" on the I-array) and saw that the focal plane temperature warmed from -119.87 to -119.38 during the run. Also, please read a note from Norbert Schulz (nss@space.mit.edu) (see "Comments from experts" bellow). *********** Photon Page ************ Acis OBSID DETECTOR GRATING TARGET ANALYSIS --------------------------------------------------------- 723 ACIS-S NONE 4U0142+61 OK bright point source 803 ACIS-S NONE NGC 4374 OK 853 ACIS-I NONE BAL1556+3217 OK 194 ACIS-I NONE CAS A, CHIP I3 OK bright 543 ACIS-I NONE MS1455.0+2232 OK 962 NO INFORMATION OK 83 ACIS-S NONE RXJ 0439.8-6809 OK 852 ACIS-I NONE BAL1312+2319 OK 927 ACIS-I NONE CL0848.6+4453 OK 637 ACIS-I NONE RHO OPH A OK 551 ACIS-I NONE MS2053.7-0449 OK 808 ACIS-I NONE NGC 4736 OK 776 AICS-I NONE 0409-67.5 OK very bright ********** Comments from experts ********* >From Norbert Schulz: I looked through -110 C and -120 C external cal source data in order to determine the temperature sensitivity of the energy scale. I used nodes 0 on I0, I1, and S3 as devices and took data FAR away from readout where CTI is strongest (and therefore temperature sensitivity) device energy PHA(-110 C) PHA(-120 C) Dgain(%) (keV) (ADU) (ADU) I0 1.487 288 305 5.9 4.510 977 1012 3.6 5.898 1300 1345 3.5 I1 1.487 282 305 8.2 4.510 982 1007 2.6 5.898 1285 1334 5.9 S3 1.487 309 304 1.6 4.510 981 971 1.0 5.898 1291 1280 0.9 >From this we see that a) The sensitivity of the FI devices towards temperature changes is larger than in th BI devices, which is understandable because CTI is much higher. b) Sensitivity seems higher at low energies, we should therefore use the values at 1.5 kev for reference The accuracy of the data above is +/-0.2 ADU, the percentages are for a temperature span of 10 C. Sensitivity ===> FI devices: changes in energy scale per degree K is 0.7% ===> BI devices: changes in energy scale per degree K is 0.2% Since the data were taken far away from the readout (although for ACIS-I this would be the aim point) this is the worst case scenario. By averaging over the entire node (at readout there is no sensitivity) we would get: ===> FI devices: changes in energy scale per degree K is 0.4% ===> BI devices: changes in energy scale per degree K is 0.1% Clearly that means that in case of the BI we don't have to worry too much about temperature changes. In the case of FI devices a change of 3 K will cause >1% change in the energy scale, which is a tolerable limit. The trend of the data show that it get worse below 1.5 keV, i.e. larger changes than 3 K are clearly not desirable.