Accepted Cycle 12 Observing Proposals

CLUSTERS OF GALAXIES

Proposal Number	Subject Category	PI Name	Title
12800143	CLUSTERS OF GALAXIES	Gitti	Investigating AGN feedback in cool cores detected in H\alpha
12800164	CLUSTERS OF GALAXIES	Morris	Extreme Mergers from the Massive Cluster Survey
12800244	CLUSTERS OF GALAXIES	Kraft	A Deep Chandra Observation of the Hot Cluster around 3C 438
12800274	CLUSTERS OF GALAXIES	Ebeling	The Bullet Cluster Reloaded? An in-depth study of two post-collision cluster mergers
12800326	CLUSTERS OF GALAXIES	Markevitch	A SHOCK FRONT IN A521 AND A NEW METHOD OF MEASURING THE INTRACLUSTER MAGNETIC FIELD
12800339	CLUSTERS OF GALAXIES	Russell	Revealing the ICM transport processes with the bow shock, upstream shock and turbulent wake in Abell 2146
12800344	CLUSTERS OF GALAXIES	Sanders	A deep look at PKS 0745-191 and its cluster environment
12800358	CLUSTERS OF GALAXIES	Pierre	X-ray characterisation of the most distant spectroscopically confirmed cluster of galaxies
12800403	CLUSTERS OF GALAXIES	Maughan	Extending X-ray and Sunyaev-Zel'dovich effect calibrations to low mass galaxy clusters
12800409	CLUSTERS OF GALAXIES	Rossetti	Zooming in Abell 3560: a non-cool core cluster with a bright radio-loud BCG
12800410	CLUSTERS OF GALAXIES	Sun	AGN heating and cooling in the most luminous group cool core
12800433	CLUSTERS OF GALAXIES	Kraft	A Deep {\em Chandra} Study of NGC 4472 - Gas Dynamics in the Nearest Group-Cluster Merger
12800509	CLUSTERS OF GALAXIES	Nulsen	Abell 2034: a Merger Near the Plane of the Sky
12800510	CLUSTERS OF GALAXIES	Santos	Cool core clusters at high redshift: the unique case of WARPS J1415.1+3612
12800522	CLUSTERS OF GALAXIES	Giles	The X-ray Properties of Weak-Lensing Selected Galaxy Clusters
12800525	CLUSTERS OF GALAXIES	Forman	Physics of Cluster Mergers - Coma, the Nearest Rich Cluster Merger
12800531	CLUSTERS OF GALAXIES	Clarke	Abell 2443: An Extreme Relic as a Merger Signpost?
12800532	CLUSTERS OF GALAXIES	Boehringer	Chandra Study of the X-ray Bright Distant Galaxy Cluster XMMU J0954+1738 at z=0.83
12800548	CLUSTERS OF GALAXIES	Gastaldello	A textbook cold front in Abell 1775 at sharp focus with Chandra
12800572	CLUSTERS OF GALAXIES	Miller	The Outer Limits of Clusters with Chandra and Suzaku
12800632	CLUSTERS OF GALAXIES	Hughes	Chandra Observations of the ACT Sample of SZE-Selected Galaxy Clusters
12800643	CLUSTERS OF GALAXIES	McNamara	Accretion Properties of Powerful AGN in Galaxy Clusters
12800664	CLUSTERS OF GALAXIES	Vikhlinin	A 'CENTENNIAL' SAMPLE OF THE 100 X-RAY BRIGHTEST GALAXY CLUSTERS
12800704	CLUSTERS OF GALAXIES	Sarazin	Abell 665: Determining the Connection Between Cluster Dynamics and Radio Halos
12800778	CLUSTERS OF GALAXIES	Miller	Abell 1882: A Proto-cluster at Low Redshift
12800854	CLUSTERS OF GALAXIES	Dawson	DLSCL J0916+2953: A New Transverse Cluster Merger

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800143

Title: Investigating AGN feedback in cool cores detected in H\alpha

PI Name: Myriam Gitti

Chandra has changed our understanding of the cool cores of galaxy clusters from a relatively simple place where gas is cooling and flowing toward the center to a very dynamic place where heating from the central AGN and cooling, as inferred from active star formation, molecular gas and H\alpha nebulosity, find an uneasy balance. With the aim to get a comprehensive picture of the AGN feedback mechanism, we propose to investigate the X-ray/radio interaction in a compilation of targets selected among the brightest X-ray clusters and the most luminous emitters in H\alpha, which is a promising diagnostic of cool gas in cluster cores. As part of our ongoing study we request Chandra snapshots and joint VLA observations of A2495 and A1668 for a total exposure time of 18 ks and 18 h, respectively.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
22:50:23.90	+10:53:54.70	Abell 2495	ACIS-S	NONE	8
13:03:51.40	+19:15:55.10	Abell 1668	ACIS-S	NONE	10

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800164

Title: Extreme Mergers from the Massive Cluster Survey

PI Name: Roger Morris

We propose to observe two extraordinary, high-redshift galaxy clusters from the Massive Cluster Survey. Both targets are very rare, triple merger systems (one a nearly co-linear merger), and likely lie at the deepest nodes of the cosmic web. Both targets show multiple strong gravitational lensing arcs in the cluster cores. These targets only possess very short (10ks) Chandra observations, and are unobserved by XMM-Newton. The X-ray data will be used to probe the mass distribution of hot, baryonic gas, and to reveal the details of the merger physics and the process of cluster assembly. We will also search for hints of X-ray emission from filaments between the merging clumps. Subaru and Hubble Space Telescope imaging data are in hand; we request additional HST coverage for one object.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
12:26:51.50	+21:51:15.50	MACSJ1226.8+2153	ACIS-I	NONE	130

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800244

Title: A Deep Chandra Observation of the Hot Cluster around 3C 438

PI Name: Ralph Kraft

We propose a 120 ks Chandra/ACIS-S followup observation on the hot cluster associated with the radio galaxy 3C 438 at z=0.29. This is one of the hottest, and presumably most massive, clusters in the Universe (T>13 keV). We reported the presence of a surface brightness discontinuity in the gas extending 550 kpc from the nucleus, but it was unclear whether this feature was the result of sloshing, a major cluster merger, or a nuclear outburst (Kraft et al. 2007). Whatever the cause, the energy required to move 10 keV cluster gas this distance must be incredibly powerful. We request a deeper Chandra observation of this unique hot cluster to better constrain the temperature and map the morphology of the gas. The proposed observation will definitively resolve the nature of the interaction.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
21:25:52.30	+38:00:30.00	3C 438 cluster	ACIS-S	NONE	120

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800274

Title: The Bullet Cluster Reloaded? An in-depth study of two post-collision cluster mergers

PI Name: Harald Ebeling

Detailed X-ray/lensing studies of the massive X-ray selected galaxy clusters 1E0657-56 (the "Bullet Cluster") and MACSJ0025.4-1222 have exploited the segregation of collisional and collisionless matter in cluster mergers to obtain first constraints on the self-interaction cross section of dark matter. We here propose a similar study of two newly discovered very X-ray luminous galaxy clusters from the MACS sample that have been confirmed as linear, post-collision mergers of similar or higher mass. The proposed ACIS-I and HST/ACS observations will allow an accurate mapping of collisional (X-ray gas) and collisionless matter (galaxies and, presumably, dark matter) and thus yield improved constraints on the properties of dark matter.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
01:40:02.00	-05:55:00.00	MACSJ0140.0-0555	ACIS-I	NONE	20
05:53:24.00	-33:42:30.00	MACSJ0553.4-3342	ACIS-I	NONE	75

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800326

Title: A SHOCK FRONT IN A521 AND A NEW METHOD OF MEASURING THE INTRACLUSTER MAGNETIC FIELD

PI Name: Maxim Markevitch

Shock fronts provide a unique tool to study the cluster plasma, but so far, only a few unambiguous examples have been found. We propose to confirm and quantify another candidate, an X-ray brightness edge detected in a short Chandra observation of A521 at the location of a prominent peripheral radio relic, which has one of the best multi-frequency radio datasets with VLA and GMRT. Owing to its simple geometry, this shock front will enable a novel measurement of the intracluster magnetic field, based on the width of the radio relic and the gas velocity determined from X-rays. The proposed observation will confirm that this is a shock front via the temperature measurements and by making it visually obvious. Detecting faint, sharp shock fronts in clusters is something only Chandra can do.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
04:54:22.10	-10:16:15.90	A521	ACIS-I	NONE	90

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800339

Title: Revealing the ICM transport processes with the bow shock, upstream shock and turbulent wake in Abell 2146

PI Name: Helen Russell

Shock fronts generated by galaxy cluster mergers provide a key tool for studying the cluster gas. However, unambiguous detections of shock fronts are rare and only two have previously been found, those in the Bullet cluster and Abell 520. Our recent Chandra observation of Abell 2146 has revealed that this cluster has two Mach 2 merger shock fronts and a gas structure remarkably similar to the Bullet cluster (eg. Markevitch et al. 2002). We propose a deep observation of Abell 2146 to test electron-ion equilibrium, which was found to be shorter than the Coulomb time in the Bullet cluster, and investigate the ICM transport processes by studying the complex substructures and shocks in the subcluster tail.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
15:56:14.70	+66:20:48.90	Abell 2146	ACIS-I	NONE	400

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800344

Title: A deep look at PKS 0745-191 and its cluster environment

PI Name: Jeremy Sanders

We propose to observe the PKS 0745-191 galaxy cluster, the X-ray brightest at a redshift of >0.1. In its core substantial cooling is taking place, as seen from the Ha nebula, blue light, CO and IR emission. The unusual radio source PKS0745 shows disrupted jets and is amorphous, seen in few other objects. We request a 120ks observation to study AGN feedback, reducing the size of the current regions spectrally examined to that of the radio source and optical filaments. We also request EVLA time to study the central source in detail and other sources to map the magnetic field structure in this object. Secondary aims will be to examine the pressure jump to the west of the cluster, map the metals, and test hydrostatic equilibrium by comparing X-ray and strong lensing mass measurements.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
07:47:31.30	-19:17:40.10	PKS 0745-19	ACIS-S	NONE	120

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800358

Title: X-ray characterisation of the most distant spectroscopically confirmed cluster of galaxies

PI Name: Marguerite Pierre

We propose to perform a 90 ks Chandra observation in combination with a 200 ks XMM observation of the most distant spectroscopically confirmed cluster of galaxies at z=1.6. The cluster was found in the MIR and X-ray emission detected on XMM survey-type data. The proposed observations will allow the study of the X-ray AGN population in the cluster as well as the characterisation of the spatial and spectral properties of the cluster to an accuracy better than 30% out to ~ R_500. Along with the existing multi-wavelength data set, the deep X-ray observations will add invaluable insights onto high-redshift cluster properties: morphology, dynamical/relaxation state, L-T and M-T X-ray relations, AGN formation as well clues about pre-heating rates and mechanisms.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
02:18:21.30	-05:10:27.00	IRC 0218-A	ACIS-S	NONE	90

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800403

Title: Extending X-ray and Sunyaev-Zel'dovich effect calibrations to low mass galaxy clusters

PI Name: Ben Maughan

Sunyaev-Zel'dovich effect (SZE) surveys will produce large samples of galaxy clusters for performing precision cosmology. However, SZE science is still in its infancy, and SZE probes of the intra-cluster medium (which are predicted to be excellent cluster mass proxies) must be calibrated against established X-ray measurements before they can be relied upon. This work has begun with studies of the most massive clusters known, but in this proposal we seek to extend these calibration studies to lower mass systems that are representative of the populations expected in SZE surveys. We request 167 ks of Chandra time to observe 7 galaxy clusters, completing a volume-limited sample of 14 clusters at z=0.17. All clusters have existing or scheduled observations with the SZA or OCRA SZE instruments.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
22:56:57.10	+05:32:49.20	A2507	ACIS-I	NONE	34
22:26:54.70	+25:50:56.40	A2445	ACIS-I	NONE	27
09:42:15.60	+15:22:55.20	A853	ACIS-I	NONE	26
00:06:17.30	+10:52:04.80	Z15	ACIS-I	NONE	27
17:50:16.10	+35:04:58.80	RXJ1750.2+3505	ACIS-I	NONE	20
03:01:38.20	+01:55:37.20	Z808	ACIS-I	NONE	19
12:30:48.00	+10:33:21.60	A1553	ACIS-I	NONE	14

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800409

Title: Zooming in Abell 3560: a non-cool core cluster with a bright radio-loud BCG

PI Name: Mariachiara Rossetti

We propose an observation of the central region of A3560, a non-cool core cluster, whose brightest central galaxy is very luminous in the radio band. We ask for a 20 ks observation with ACIS-S to assess the presence of a thermal corona associated with the dominant galaxy which could provide the fuel to trigger the radio emission. This observation will also allow to verify the presence of a curios ``donut'' shaped structure in the center of the cluster, which is observed in the available XMM-Newton image at the limit of its spatial resolution.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
13:32:26.00	-33:09:01.90	Abell 3560	ACIS-S	NONE	20

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800410

Title: AGN heating and cooling in the most luminous group cool core

PI Name: Ming Sun

Outbursts of SMBHs have significant impact on structure formation and evolution. Their imprint on ICM (e.g., shocks, cavities, elevated entropy) provides an historical chronicle of the SMBH activity. Because of the expected bigger impact of AGN heating on the group gas than the cluster gas, group cool cores are ideal places to study SMBH outbursts. We propose an 89 ks observation of the most X-ray luminous group cool core at z<0.05 (also the second brightest one) that only has 7 ks Chandra data. It also hosts one of the most spectacular Ha filaments in nearby groups. The requested ACIS data, in combination with the joint VLA and HST observations, will be used to examine cavities, shocks, the relation between gas in different phases and star formation, and the AGN activity history.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
14:07:29.70	-27:01:04.10	A3581	ACIS-S	NONE	89

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800433

Title: A Deep {\em Chandra} Study of NGC 4472 - Gas Dynamics in the Nearest Group-Cluster Merger

PI Name: Ralph Kraft

We propose a deep, 300 ks, Chandra/ACIS-S observation of the nearby galaxy NGC 4472. NGC 4472 is the most optically luminous galaxy of the Virgo cluster, and is the dominant member of a group falling into M87. It is the nearest, brightest example of a group being ram-pressure stripped as it falls into a cluster, and this deep observation will elucidate microphysics of the stripping process unobservable in any other object. We will measure temperature and elemental abundance variations of 4% and 15% (90% confidence), respectively, on scales as small as 250pcx250pc. We will also make a deep study of the LMXB population, and probe the dynamics of the gas flow near the Bondi radius of the central SMBH.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
12:29:46.70	+08:00:02.00	NGC 4472	ACIS-S	NONE	300

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800509

Title: Abell 2034: a Merger Near the Plane of the Sky

PI Name: Paul Nulsen

The most decisive signature of a major merger in a cluster of galaxies is the presence of well-defined merger shocks in the intracluster medium. Only two clear instances of merger shocks have been confirmed to date. A feature in the merging cluster Abell 2034 that was previously identified as a cold front is more consistent with a merger shock. We propose to obtain a deeper Chandra exposure of Abell 2034 to reveal critical features obscured by chip gaps in the existing Chandra data and to confirm the presence of a merger shock. The new data will be used to quantify the properties of the merger. The X-ray data will be combined with optical spectra of cluster galaxies to study the dynamics of this system and the impact of the merger on the galaxies.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
15:10:13.40	+33:30:43.00	Abell 2034	ACIS-I	NONE	200

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800510

Title: Cool core clusters at high redshift: the unique case of WARPS J1415.1+3612

PI Name: Joana Santos

We propose a deep (280 ks) ACIS-S Chandra observation of the cluster WARPS J1415+3612 at z=1.026. Our analysis of an archival 90 ksec ACIS-I observation revealed a peaked surface brightness profile, typical of cool-core clusters. Recent studies show that, while there is no evolution in the cool-core fraction up to z=0.4, there is an apparent deficit of very strong cool-core clusters out to z=1.3. In our study, WARPSJ1415 is shown to be the most prominent cool core at z>1. With the proposed observation we want to measure, for the first time at z=1, a high-quality temperature and metallicity profile for WARPSJ1415 in order to directly compare its properties with those of cool-core clusters at z<0.5. We will also derive accurate DM and density profiles to be compared with lensing studies.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
14:15:11.20	+36:12:04.00	WARPS J1415.1+3612	ACIS-S	NONE	280

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800522

Title: The X-ray Properties of Weak-Lensing Selected Galaxy Clusters

PI Name: Paul Giles

The selection functions of cluster samples used for cosmological studies has a crucial impact on the reliability of derived parameters. There is growing evidence that optically selected clusters are underluminous in X-rays, indicating larger X-ray selection biases than previously thought. We propose to address this with Chandra observations (totalling 231 ks) of 8 clusters selected in a Subaru weak lensing (WL) survey. This will complete a sample of 10 clusters that will be used to systematically study the X-ray properties of clusters detected independently of their baryonic content. We will measure the scaling relations of the X-ray properties (e.g. Lx, kT, Mgas, Yx), study the morphology/structure, and test the calibration of X-ray mass proxies for a sample of WL-selected clusters.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
11:35:38.40	+30:09:36.00	SLJ1135.6+3009	ACIS-I	NONE	11
16:47:47.50	+34:55:13.00	SLJ1647.7+3455	ACIS-I	NONE	14
12:04:22.90	-03:50:55.00	SLJ1204.4-0351	ACIS-I	NONE	23
08:50:31.70	+45:12:12.00	SLJ0850.5+4512	ACIS-I	NONE	29
13:37:43.70	+38:00:57.00	SLJ1337.7+3800	ACIS-I	NONE	34
13:35:45.60	+37:31:48.00	SLJ1335.7+3731	ACIS-I	NONE	27
16:02:52.80	+43:35:24.00	SLJ1602.8+4335	ACIS-I	NONE	46
16:34:12.00	+56:39:36.00	SLJ1634.1+5639	ACIS-I	NONE	47

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800525

Title: Physics of Cluster Mergers - Coma, the Nearest Rich Cluster Merger

PI Name: William Forman

We propose a 45 ks ACIS-I observation of the massive merging subcluster associated with the cD galaxy NGC4839 in the Coma cluster. Complementing a new XMM-Newton observation, the Chandra investigation will provide the key high angular resolution to 1) precisely measure the structure and density jump of the NGC4839 merger cold front and 2) measure the structure and density jump of the "sheath" surrounding the infalling subcluster, a likely shock. With XMM-Newton derived temperatures, we will measure pressures across the cold front and in the shock. Finally, the Chandra pointing will 1) resolve the radio cavities in the center of NGC4839, 2) determine the SMBH radiative luminosity, and 2) detect any hot corona around the central AGN that may be a source of fuel.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
12:57:24.10	+27:29:47.00	NGC4839	ACIS-I	NONE	45

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800531

Title: Abell 2443: An Extreme Relic as a Merger Signpost?

PI Name: Tracy Clarke

Our low frequency radio observations of Abell 2443 show the first strong evidence of merger activity, including the discovery of a (rare) ultra-steep spectrum relic. We propose to use the sensitivity and resolution of Chandra to confirm and characterize the merger and examine its relation to the radio relic. The detailed ICM morphology will provide insight into the merger dynamics. The confirmation and study of new objects of this class can help establish correlations between the radio properties and the cluster dynamical state, and discriminate among the proposed theoretical models of their origins. Since the radio relic has an unusually steep spectrum, it may be particularly useful in probing the physical properties of the relation between the merger and relic formation.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
22:26:04.50	+17:21:59.40	Abell 2443	ACIS-S	NONE	16

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800532

Title: Chandra Study of the X-ray Bright Distant Galaxy Cluster XMMU J0954+1738 at z=0.83

PI Name: Hans Boehringer

We propose a deep CHANDRA observation (70 ks) of the X-ray brightest galaxy cluster discovered in the cleanest 20 deg^2 of our XDCP survey at redshift >0.8 in the XMM-Newton archive, XMMU J0954+1738 with L_X~1.5x10^44 erg/s (0.5 to 2.0 keV) and z=0.83. The main objective of the proposed observation is to secure precise values of the global cluster parameters which can also be used as mass proxies: X-ray luminosity, temperature, gas mass and the Y_X parameter. These properties and a good mass estimate are important for our detailed study of high-z cluster galaxy populations, to establish scaling relations of clusters at z>0.8, and to contribute to the compilation of a sample of well characterized clusters at these redshifts for cosmological studies.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
09:54:17.10	+17:38:05.90	XMMU J0954+1738	ACIS-S	NONE	70

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800548

Title: A textbook cold front in Abell 1775 at sharp focus with Chandra

PI Name: Fabio Gastaldello

We propose a 100 ks Chandra observation of the merging cluster Abell 1775 to investigate in detail the spectacular features shown by a XMM observation. The cluster has an extremely sharp cold front in an angular sector of 60 degrees while at wider angles it seems to mix with the ambient hotter medium through the development of a large scale Kelvin-Helmholtz (KH) instability. Further away from the direction of motion excess emission is present likely resulting from the stripping of the gas. The high resolution Chandra observation will allow to determine accurately the core velocity from X-rays, confirm the suggestion of a KH instability and study the X-ray tail at the highest spatial resolution possible.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
13:41:48.80	+26:22:20.80	Abell 1775	ACIS-S	NONE	100

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800572

Title: The Outer Limits of Clusters with Chandra and Suzaku

PI Name: Eric Miller

We propose ACIS-I snapshot observations of the outskirts of three galaxy clusters. When combined with awarded and existing Suzaku observations of overlapping regions, these data will enable us to identify X-ray point sources (cluster and background AGN) that are undetectable by Suzaku and that dominate the uncertainty in the X-ray background. The combination of Chandra and Suzaku data is vital to our search for non-equilibrium structures in these seemingly relaxed systems. In addition, we will obtain a full census of cluster AGN out to r200, thereby improving constraints on evolution of the AGN fraction in these systems.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
14:25:02.80	+37:37:43.80	A1914_Field2	ACIS-I	NONE	5
14:27:02.90	+38:01:11.80	A1914_Field3	ACIS-I	NONE	5
14:25:03.80	+38:00:15.80	A1914_Field4	ACIS-I	NONE	5
16:33:27.20	+05:43:57.60	A2204_Field1	ACIS-I	NONE	5
16:32:04.70	+05:43:17.60	A2204_Field2	ACIS-I	NONE	5
16:33:25.00	+05:24:13.60	A2204_Field3	ACIS-I	NONE	5
16:32:00.90	+05:24:21.60	A2204_Field4	ACIS-I	NONE	5
06:06:41.90	-35:27:52.60	RXCJ0605_Field1	ACIS-I	NONE	5
06:05:06.30	-35:28:40.70	RXCJ0605_Field2	ACIS-I	NONE	5
06:06:43.70	-35:07:44.60	RXCJ0605_Field3	ACIS-I	NONE	5
06:05:02.00	-35:08:24.60	RXCJ0605_Field4	ACIS-I	NONE	5

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800632

Title: Chandra Observations of the ACT Sample of SZE-Selected Galaxy Clusters

PI Name: John Hughes

We propose to obtain Chandra observations of a complete sample of galaxy clusters detected by the Atacama Cosmology Telescope (ACT) using the Sunyaev-Zeldovich effect (SZE). The proposed ACIS-I observations of 14 massive, newly-discovered SZE clusters will provide a precision calibration of the SZE signal versus mass correlation out to redshifts of 1. This effort is part of an intensive multi-wavelength campaign to produce an unbiased, well-observed sample of massive galaxy clusters out to high redshifts for cosmological investigations. These proposed observations will allow us to link directly the X-ray and SZE properties of massive clusters, so that cosmologists can reliably utilize the new large cluster samples that are being accumulated from both Chandra and the new SZ experiments.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
01:02:53.00	-49:15:16.90	ACT J0102-4915	ACIS-I	NONE	60
04:38:21.00	-54:19:48.10	ACT J0438-5419	ACIS-I	NONE	20
02:45:28.50	-53:02:05.00	ACT J0245-5302	ACIS-I	NONE	20
06:16:37.30	-52:27:37.10	ACT J0616-5227	ACIS-I	NONE	39
02:35:50.70	-51:21:55.40	ACT J0235-5121	ACIS-I	NONE	20
02:32:50.30	-52:57:50.00	ACT J0232-5257	ACIS-I	NONE	20
05:59:46.00	-52:50:21.40	ACT J0559-5249	ACIS-I	NONE	115
03:04:19.10	-49:21:53.50	ACT J0304-4921	ACIS-I	NONE	23
02:37:04.70	-49:38:39.30	ACT J0237-4939	ACIS-I	NONE	42
06:41:37.80	-49:46:54.70	ACT J0641-4948	ACIS-I	NONE	20
02:15:15.10	-52:12:53.90	ACT J0215-5212	ACIS-I	NONE	21
02:17:10.70	-52:44:32.00	ACT J0217-5245	ACIS-I	NONE	20
03:46:58.60	-54:39:31.00	ACT J0346-5438	ACIS-I	NONE	37
07:07:08.00	-55:23:37.00	ACT J0707-5522	ACIS-I	NONE	20

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800643

Title: Accretion Properties of Powerful AGN in Galaxy Clusters

PI Name: Brian McNamara

We propose to obtain a deep image of the galaxy cluster Zw 2701. A short archival image has revealed evidence for for cavities in its hot atmosphere with a total mechanical energy potentially exceeding 10^60 erg. Powerful AGN place high energetic demands on the central engine. They are therefore able to provide meaningful constraints on accretion power and black hole spin models. Powerful AGN are able to drive large-scale outflows of cool, metal-enriched gas, which can be measured and compared to hydrodynamic jet models, and they have great potential to reveal how bulges and SMBHs coevolve. Finally, they may harbor ``ultramassive'' black holes with masses exceeding ten billion solar masses.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
09:52:49.00	+51:53:06.00	Zw 2701	ACIS-S	NONE	100

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800664

Title: A 'CENTENNIAL' SAMPLE OF THE 100 X-RAY BRIGHTEST GALAXY CLUSTERS

PI Name: Alexey Vikhlinin

We propose to observe 14 low-redshift galaxy clusters selected in the ROSAT All-Sky Survey. These observation will complete a sample of 100 X-ray brightest clusters in the extragalactic sky. This sample will serve as an excellent reference point for upcoming SZ surveys, provide interesting cosmological data by itself, and also set the stage for subsequent observations of interesting structures which will be discovered in these objects which have never before been imaged with a sensitive X-ray telescope.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
22:05:36.90	-05:36:06.00	A2415	ACIS-I	NONE	10
05:48:37.80	-25:28:49.30	A548e	ACIS-I	NONE	10
20:34:43.30	-35:48:55.90	A3695	ACIS-I	NONE	10
12:52:33.60	-31:16:16.00	RXJ1252.5-3116	ACIS-I	NONE	10
22:35:44.30	+01:27:47.10	A2457	ACIS-I	NONE	10
02:46:00.60	+36:53:00.50	A376	ACIS-I	NONE	10
23:44:18.30	-04:23:04.30	RXJ2344.3-042	ACIS-I	NONE	10
22:14:34.30	-10:22:52.20	A2426	ACIS-I	NONE	10
23:50:50.20	+06:09:21.30	A2665	ACIS-I	NONE	10
19:58:12.80	-30:10:58.60	RXJ1958.2-3011	ACIS-I	NONE	10
13:36:06.10	+59:12:06.80	A1767	ACIS-I	NONE	10
13:59:16.90	+27:58:50.80	A1831	ACIS-I	NONE	10
17:09:41.70	+34:25:25.10	A2249	ACIS-I	NONE	10
10:17:24.10	-10:40:52.20	A970	ACIS-I	NONE	10

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800704

Title: Abell 665: Determining the Connection Between Cluster Dynamics and Radio Halos

PI Name: Craig Sarazin

Abell 665 is a hot, massive cluster which is undergoing a major merger. The previous, short Chandra observations have revealed a surface brightness discontinuity to the south, which has been described as either a cold front or a shock; the existing spectra allow either interpretation. There is a hot region to the south of the discontinuity which may be post-shock gas, but the merger bow shock has not been located. Recently, we have found density jumps to the east, west, and north which may be Mach number ~1.5 shocks. A665 hosts a powerful radio halo, which seems to extend to these shock regions. We propose a longer Chandra observation to study the features revealed in the shorter exposures, and to determine the dynamical state and connection to the radio halo in this cluster.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
08:30:53.30	+65:50:02.40	Abell 665	ACIS-I	NONE	100

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800778

Title: Abell 1882: A Proto-cluster at Low Redshift

PI Name: Christopher Miller

We propose to use Chandra to determine whether the A1882 super-group is an example of a low-redshift proto-cluster. A1882 is a dynamically bound collection of three or four galaxy groups. The groups will collapse into a typical galaxy cluster in the future. Our current data show that the galaxies within A1882 have on-going star-formation, AGN activity, even in the group core regions. We propose to collect enough X-ray photons to measure the temperatures and Fe/Si abundances in 3-5 annuli around each group.We will look for evidence of metal and temperature gradients, and in combination with the optical data, infer the physical mechanisms which might (or might not) be responsible for the enriched nature of galaxy clusters.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
14:15:06.60	-00:29:27.60	A1882a	ACIS-S	NONE	100
14:14:24.50	-00:22:37.90	A1882b	ACIS-S	NONE	40
14:14:57.90	-00:20:55.70	A1882c	ACIS-S	NONE	50

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 12800854

Title: DLSCL J0916+2953: A New Transverse Cluster Merger

PI Name: William Dawson

Merging clusters of galaxies are beginning to provide constraints on fundamental physics, such as the dark matter self-interaction cross-section and the matter/antimatter ratio. We request joint Chandra and HST imaging to examine a merger at z=0.53 which we have identified optically and spectroscopically confirmed. Our optical data and weak lensing mass map clearly show three sub-clusters within the same redshift range, while our SZ data are consistent with an offset between the hot ICM and sub-clusters; Combined HST and Chandra imaging are needed to confirm this offset and provide accurate displacements between X-ray-emitting gas, galaxies, and mass which can constrain the physics of merging clusters. The requested observations will also facilitate a wide range of non-merger science.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
09:16:15.00	+29:51:00.00	DLSCL J0916+2953	ACIS-I	NONE	40

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