Accepted Cycle 11 Observing Proposals

EXTRAGALACTIC DIFFUSE EMISSION & SURVEYS

Proposal Number	Subject Category	PI Name	Title
11900125	EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS	Levan	A survey of dark gamma-ray burst hosts
11900514	EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS	Gultekin	COMBH: Chandra Observations of M-sigma Black Holes
11900760	EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS	Cheung	Identifying Unidentified Fermi-LAT Objects (UFOs) at High-Latitude

Subject Category: EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Number: 11900125

Title: A survey of dark gamma-ray burst hosts

PI Name: Andrew Levan

A fraction of gamma-ray bursts (GRBs) are dark in the optical, often suggesting suppression relative to the X-ray flux. These bursts may originate in highly obscured environments, different from those of the optically bright GRBs. We propose to continue our earlier program by conducting a set of modest ToO observations of these GRBs. Chandra observations will provide precise burst positions (~0.5") and, unlike Swift-XRT observations will enable the unambiguous location of the host galaxy. Subsequent HST imaging will provide broadband magnitudes, colours and morphologies. Our early results suggest that dark bursts hosts can be markedly different from those of the bright population, and motivates the need to gather a larger sample to accurately constrain their properties.

Target Name	Det.	Grating	Exp.Time
Dark-GRB1	ACIS-S	NONE	15
Dark-GRB2	ACIS-S	NONE	15
Dark-GRB3	ACIS-S	NONE	15

Subject Category: EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Number: 11900514

Title: COMBH: Chandra Observations of M-sigma Black Holes

PI Name: Kayhan Gultekin

Galaxies with dynamically-measured central BH masses allow us to understand BH accretion, jets, and interactions between BHs and host galaxies with a clarity not possible in random surveys. By measuring true Eddington fractions, we can calculate the energy in radiation vs mechanical jet energy and the efficacy of BHs in heating nuclear regions and affecting star formation. Remarkably, 1/3 of SMBHs making up the M-sigma relation have been poorly observed or totally unobserved with Chandra. We propose a survey of 15 M-sigma galaxies to complete the sample of reliable M-sigma SMBHs. For each galaxy we propose to obtain 30-60 ks exposures and an hour-long VLA observation. This survey will test and extend the fundamental plane of BH activity and facilitate studies of the origin of M-sigma.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
03:19:41.10	-19:24:40.90	NGC1300	ACIS-S	NONE	30
09:13:43.00	+76:28:31.20	NGC 2748	ACIS-S	NONE	30
09:12:24.40	+35:01:39.10	NGC2778	ACIS-S	NONE	30
12:20:17.80	+75:22:15.20	NGC4291	ACIS-S	NONE	30
12:51:48.00	-10:27:17.00	NGC4742	ACIS-S	NONE	30
13:19:31.70	-12:39:25.10	NGC5077	ACIS-S	NONE	30
14:21:03.70	+03:16:15.60	NGC5576	ACIS-S	NONE	30
10:48:16.90	+12:37:45.40	NGC3384	ACIS-S	NONE	30
12:30:57.70	+12:16:13.30	NGC4486A	ACIS-S	NONE	30
12:28:60.00	+13:58:42.80	NGC4459	ACIS-S	NONE	30
12:39:55.90	+10:10:33.90	NGC4596	ACIS-S	NONE	30
23:00:59.90	+30:08:41.60	NGC7457	ACIS-S	NONE	30

Subject Category: EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Number: 11900760

Title: Identifying Unidentified Fermi-LAT Objects (UFOs) at High-Latitude

PI Name: Chi (Teddy) Cheung

We propose a Chandra study of 8 high Galactic latitude gamma-ray sources in the Fermi-LAT bright source list. These sources are currently unidentified, i.e., they are not clearly associated with established classes of gamma-ray emitters like blazars and pulsars. The proposed observations will determine the basic properties (fluxes, positions, hardness ratio/spectra) of all X-ray sources down to a 0.3-10 keV flux limit of 1.5e-14 erg/cm2/s within the Fermi-LAT localization circles. This will enable further follow-up at other wavelengths, with the ultimate goal to reveal the nature of these enigmatic gamma-ray sources.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
16:53:40.80	-01:59:49.20	J1653.4-0200	ACIS-I	NONE	20
22:14:42.00	+30:02:45.60	J2214.8+3002	ACIS-I	NONE	20
22:41:53.80	-52:37:04.80	J2241.7-5239	ACIS-I	NONE	20
13:11:49.70	-34:28:37.20	J1311.9-3419	ACIS-I	NONE	20
23:39:37.20	-05:33:18.00	J2339.8-0530	ACIS-I	NONE	20

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