Accepted Cycle 15 Observing Proposals

EXTRAGALACTIC DIFFUSE EMISSION & SURVEYS

Proposal Number	Subject Category	PI Name	Type	Time (ks)	Title
15900132	EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS	Brandt	XVP	4000	The Chandra Deep Field-South: A Peerless Ultradeep Survey for Exploring the Distant X-ray Universe
15900142	EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS	Townsley	XVP	2000	The Tarantula -- Revealed by X-rays (T-ReX): A Definitive Chandra Investigation of 30 Doradus
15900275	EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS	Ajello	GO	15	The largest complete sample of Local AGN
15900454	EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS	Daddi	GO	96	Hot gas emission and AGN-galaxy coevolution at the dawn of cluster formation
15900537	EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS	Martini	GO	100	The growth of the most massive black holes and galaxies: A study of AGN in an overdensity at z=2.53.
15900685	EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS	Levan	TOO	60	The demographics of dark gamma-ray burst hosts

Subject Category: EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Number: 15900132

Title: The Chandra Deep Field-South: A Peerless Ultradeep Survey for Exploring the Distant X-ray Universe

Type: XVP Total Time (ks): 4000

PI Name: William Brandt

We propose to push the CDF-S exposure to 8 Ms to create a peerless ultradeep survey for exploring the distant X-ray universe. The powerful combination of improved sensitivity and improved photon statistics will (1) determine how obscured SMBHs grow and co-evolve with galaxies through the z ~ 1-4 era of massive galaxy assembly; (2) constrain the majority AGN population in the first galaxies at z ~ 4-8; and (3) clarify the evolution of X-ray binary populations in high-redshift starburst and normal galaxies. The proposed observations target parameter space that has never been probed by X-ray surveys and will be unequaled for decades. They will also be critical for complementing future ultradeep surveys with, e.g., ALMA, JWST, and ELTs.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
03:32:28.10	-27:48:26.40	Chandra Deep Field-South	ACIS-I	NONE	3000

Subject Category: EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Number: 15900142

Title: The Tarantula -- Revealed by X-rays (T-ReX): A Definitive Chandra Investigation of 30 Doradus

Type: XVP Total Time (ks): 2000

PI Name: Leisa Townsley

30 Doradus is the most important star-forming complex in the Local Group, offering a microscope on starburst astrophysics. At its heart is R136, the most massive resolved stellar cluster, containing the most massive stars known. Across 30 Dor's 250-pc extent, stellar winds and supernovae have carved its ISM into an amazing display of arcs, pillars, and bubbles. So far, Chandra has devoted only 114 ks to this iconic target, limiting our studies just to the most massive stars and large-scale diffuse phenomena. This deep observation will finally exploit Chandra's fine spatial resolution to study ISM interfaces on 1--10 pc scales, the full complement of massive stars, and the brightest pre-main sequence stars that trace 25 Myrs of star formation in this incomparable nearby starburst.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
05:38:42.40	-69:06:02.90	30 Doradus	ACIS-I	NONE	2000

Subject Category: EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Number: 15900275

Title: The largest complete sample of Local AGN

Type: GO Total Time (ks): 15

PI Name: Marco Ajello

We propose a quick snapshot program with Chandra to observe the remaining 3 AGN detected by BAT that do not have any X-ray observation in the 0.1-10 keV band. These AGN are expected to be absorbed by 23

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
04:55:54.00	-75:31:24.60	SWIFT J0455.8-753	ACIS-I	NONE	5
09:20:04.50	+37:11:03.80	SWIFT J0920.0+3711	ACIS-I	NONE	5
20:21:48.30	+44:00:00.00	SWIFT J2021.8+4400	ACIS-I	NONE	5

Subject Category: EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Number: 15900454

Title: Hot gas emission and AGN-galaxy coevolution at the dawn of cluster formation

Type: GO Total Time (ks): 96

PI Name: Emanuele Daddi

We propose 96ks Chandra observations (tripling the available integration) in the field of the cluster CL J1449+0856 at z=2, the most distant X-ray detected and spectroscopically confirmed cluster. The proposed observations will allow us to confirm the presence of a hot atmosphere with S/N>3-4 directly with Chandra, measure its luminosity and hence infer the total (dark) mass of the cluster. With 3-times deeper sensitivity for point source detection we will study in detail the AGN activity in the structure. A wealth of supporting observations at all wavelengths, comparable to prime 'deep fields', guarantees the scientific return of the Chandra data.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
14:49:14.00	+08:56:21.00	CL J1449+0856	ACIS-S	NONE	96

Subject Category: EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Number: 15900537

Title: The growth of the most massive black holes and galaxies: A study of AGN in an overdensity at z=2.53.

Type: GO Total Time (ks): 100

PI Name: Paul Martini

Chandra observations of two cluster progenitor candidates at z>2 suggest that luminous AGN may be more common in dense environments at high redshift. This is starkly different from the local universe, where luminous AGN are less common in clusters of galaxies. We propose to measure the AGN fraction in a substantial new overdensity at z=2.53 with a 100ks ACIS-I observation. Based on the large population of Halpha-emitters in this region, we expect to identify 6-13 luminous AGN, and thus substantially increase the number of luminous AGN in substantial overdensities at z>2. We will use these data to quantify the correlation between AGN and environment, and thus study the early evolution of the most massive galaxies and supermassive black holes that reside in massive clusters today.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
16:01:17.30	-00:28:47.00	4C -00.62	ACIS-I	NONE	100

Subject Category: EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Number: 15900685

Title: The demographics of dark gamma-ray burst hosts

Type: TOO Total Time (ks): 60

PI Name: Andrew Levan

Dark gamma-ray bursts (GRBs) -- where the optical emission is apparently suppressed -- can only be reliably localized by their X-ray afterglows. Here we propose to continue a survey using the sensitivity and point spread function of Chandra to precisely pinpoint the GRB locations, and HST to locate and study the host galaxies. Our results to date are suggestive of most dark GRBs originating in more luminous galaxies than "bright" GRBs. Our new observations will increase the statistical certainty of this result, while simultaneously allowing us to more precisely identify the minority of dark GRBs which most likely originate from the highest redshifts.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
		DARK-GRB1	ACIS-S	NONE	15
		DARK-GRB1	ACIS-S	NONE	15

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