Accepted Cycle 10 Large / Very Large Proposals

Proposal Number	Subject Category	PI Name	Type	Time (Ks)	Title
10200509	STARS AND WD	ZHEKOV	LP	300	Testing the Colliding Wind Paradigm: X-rays from the Wolf-Rayet Binary System WR 147
10400827	BH AND NS BINARIES	Homan	LP	323	The cooling neutron star in the super-Eddington accretor XTE J1701-462
10500327	SN, SNR AND ISOLATED NS	Reynolds	LP	250	An Extensive Study of the Youngest Galactic Supernova Remnant G1.9+0.3
10500437	SN, SNR AND ISOLATED NS	Chakrabarty	LP	366	The Spin and Magnetic Moment of the Neutron Star in Cassiopeia A
10500687	SN, SNR AND ISOLATED NS	Hughes	LP	750	A Deep Cycle 10 Chandra Observation of the Tycho Supernova Remnant
10500817	SN, SNR AND ISOLATED NS	Pavlov	LP	440	The Unique Dynamical Vela Pulsar Wind Nebula
10500824	SN, SNR AND ISOLATED NS	Bauer	LP	500	A Deep HETG Probe of the CSM Interaction in SN1996cr
10610785	NORMAL GALAXIES: DIFFUSE EMISSION	Strickland	LP	480	Wide, deep and sharp: A comprehensive observation of M82, the exemplar of starburst activity
10700504	ACTIVE GALAXIES AND QUASARS	Birkinshaw	LP	420	The multi-faceted X-ray activity of low-redshift active galaxies
10700584	ACTIVE GALAXIES AND QUASARS	Turner	LP	320	Deconstructing AGN X-ray Spectra - Time for a Paradigm Shift?
10800641	CLUSTERS OF GALAXIES	McNamara	LP	500	A Deep Image of the Most Powerful Cluster AGN Outburst
10800762	CLUSTERS OF GALAXIES	Stanford	LP	309	The Role of AGN in Massive Galaxy Formation
10800779	CLUSTERS OF GALAXIES	Blanton	LP	500	Shocks, Ripples, and Bubbles: A Very Deep Observation of Abell 2052
10900836	EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS	Fang	LP	500	A Benchmark Observation of the Warm-Hot Intergalactic Medium

Subject Category: STARS AND WD

Proposal Number: 10200509

Title: Testing the Colliding Wind Paradigm: X-rays from the Wolf-Rayet Binary System WR 147

PI Name: Svetozar ZHEKOV

We propose a deep HETG exposure of the Wolf-Rayet binary system WR 147. The excellent gratings and zero-order data will be used to put tight constraints on the validity of the colliding stellar wind (CSW) mechanism assumed responsible for the X-rays from this object. The detection of broad emission lines with profiles and centroids in agreement with synthetic colliding wind spectra, along with confirmation of the spatially extended X-ray emission reported from the previous short HRC-I exposure, would support the colliding wind picture. On the other hand, narrow (or unresolved) unshifted emission lines would require an interpretation other than CSW. Thus, this study will be the most rigorous test of the CSW paradigm in a WN+OB binary so far.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
20:36:43.70	+40:21:07.30	WR 147	ACIS-S	HETG	300

Subject Category: BH AND NS BINARIES

Proposal Number: 10400827

Title: The cooling neutron star in the super-Eddington accretor XTE J1701-462

PI Name: Jeroen Homan

Observing the cooling of neutron stars that are reheated by accretion provides new insights into neutron star structure. A detailed and efficient study of this cooling requires the use of Chandra. Here we propose to continue our ongoing monitoring campaign of the neutron star binary XTE J1701-462, a unique system that accreted at super- and near Eddington luminosities for more than 1.5 years before recently returning to quiescence. Our goal is to study the cooling of the surprisingly hot neutron star and also the evolution of the enigmatic non-thermal spectral component in unprecedented detail. Our ongoing strategy of frequent observations (every ~2.5 months) is necessary to test the most recent cooling models. We therefore request five ACIS-S observations for a total of 323 ks.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
17:00:58.50	-46:11:08.60	XTE J1701-462	ACIS-S	NONE	38
17:00:58.50	-46:11:08.60	XTE J1701-462	ACIS-S	NONE	49
17:00:58.50	-46:11:08.60	XTE J1701-462	ACIS-S	NONE	62
17:00:58.50	-46:11:08.60	XTE J1701-462	ACIS-S	NONE	76
17:00:58.50	-46:11:08.60	XTE J1701-462	ACIS-S	NONE	98

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 10500327

Title: An Extensive Study of the Youngest Galactic Supernova Remnant G1.9+0.3

PI Name: Stephen Reynolds

We have recently discovered that the smallest Galactic supernova remnant (SNR) in angular size, G1.9+0.3, is the youngest (known) Galactic SNR, with an age of about 100 years. The X-ray spectrum is lineless, well described by synchrotron emission with the highest rolloff frequency ever reported for a SNR. We propose a 500 ks Large Project observation of this unique object, which fills in a gap between SN 1987A (21 yr old) and Cas A (about 330). We wish to study detailed morphology, to compare with the 3 other Galactic synchrotron- dominated SNRs; spectra, to search for spatial variations and thermal emission; and variability, using this study for the first epoch. This object has enormous potential for the study of SNR hydrodynamics and strong-shock physics.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
17:48:45.00	-27:10:00.00	G1.9+0.3	ACIS-S	NONE	250

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 10500437

Title: The Spin and Magnetic Moment of the Neutron Star in Cassiopeia A

PI Name: Deepto Chakrabarty

How do the spin and magnetic moment of a neutron star relate to the properties of its massive progenitor and the supernova explosion? The best opportunity to study this question is the Cas A point source, the youngest known (300 yr) Galactic compact object. Its spectrum is unlike the classical Crab pulsar's, but is instead similar to both the more strongly magnetic "magnetars" and more weakly magnetic young pulsars. Much has been inferred about its progenitor and the supernova explosion from detailed studies of the supernova remnant. We propose to obtain a 500 ks HRC-S observation of the Cas A central point source, combining 350 ks of GO time and 150 ks of GTO time, in order to search for coherent pulsations down to the practical sensitivity limit of any current X-ray mission.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
23:23:27.90	+58:48:42.50	Cas A CCO	HRC-S	NONE	350

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 10500687

Title: A Deep Cycle 10 Chandra Observation of the Tycho Supernova Remnant

PI Name: John Hughes

We propose to obtain a very deep observation of the Tycho supernova remnant. Our observational goals include investigating the nature and origin of Fe-rich ejecta knots, and studying the spatial, spectral and temporal evolution of the nonthermal emission from the forward shock. Tycho is the ideal remnant for studies of cosmic-ray modified dynamics and for investigating key features of Type Ia supernova physics.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
00:25:19.00	+64:08:10.00	Tycho's SNR	ACIS-I	NONE	750

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 10500817

Title: The Unique Dynamical Vela Pulsar Wind Nebula

PI Name: George Pavlov

Chandra observations of the Vela pulsar-wind nebula (PWN) have revealed intriguing features in its structure and shown that the PWN brightness, shape, and spectrum change on a timescale as short as one week. Taking advantage of the known variability timescale, we propose a series of optimally sequenced observations to understand the PWN topology, dynamics, spectral structure, and interaction with the ambient matter.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
08:35:20.70	-45:10:35.70	Vela PWN	ACIS-S	NONE	320

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 10500824

Title: A Deep HETG Probe of the CSM Interaction in SN1996cr

PI Name: Franz Bauer

SN1996cr is one of the closest and X-ray brightest SNe detected on the sky. Like SN1987A, it appears to have exploded into a wind-blown bubble, sparking a unique temporal evolution wherein its X-ray flux has increased for >8 years now. Serendipitous HETG data allow us to identify several strong, broad, asymmetric emission-line complexes in SN1996cr, although their low-signal leaves much to interpretation. We propose a deep HETG observation of SN1996cr to resolve these emission lines and elucidate their nature (velocity structure, line diagnostics, abundances). It is imperative to observe SN1996cr while it remains bright, as it is the only SN beside SN1987A where such an observation is practical and in many ways is more representative of CSM-interacting core-collapse SNe.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
14:13:10.00	-65:20:44.50	SN1996cr	ACIS-S	HETG	500

Subject Category: NORMAL GALAXIES: DIFFUSE EMISSION

Proposal Number: 10610785

Title: Wide, deep and sharp: A comprehensive observation of M82, the exemplar of starburst activity

PI Name: David Strickland

We propose to observe M82, the exemplar of starburst and superwind activity, with a mosaic of deep ACIS-S observations that will cover the starburst region, the galactic disk and much of the extended superwind. The region of highest resolution (FWHM < 1.5") will cover the same field of view as recent deep HST and Spitzer observations. It will be the most data-rich X-ray study of a starburst galaxy ever (>1E6 counts), and will greatly advance our knowledge of the soft X-ray-emitting gas in the superwind, the very hot metal-enriched plasma within the starburst region, and the the X-ray point source population in both the starburst region and the galactic disk. It will further complement the investment made in observing M82 by the other Great Observatories, Hubble and Spitzer.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
09:55:51.30	+69:42:51.60	M82-NE	ACIS-S	NONE	120
09:55:37.60	+69:42:25.10	M82-NW	ACIS-S	NONE	120
09:55:54.20	+69:38:57.70	M82-SW	ACIS-S	NONE	120
09:56:07.80	+69:39:34.10	M82-SE	ACIS-S	NONE	120

Subject Category: ACTIVE GALAXIES AND QUASARS

Proposal Number: 10700504

Title: The multi-faceted X-ray activity of low-redshift active galaxies

PI Name: Mark Birkinshaw

We propose ACIS-I observations of Chandra-unobserved low-redshift 3CRR active galaxies and their environments. The data will complete Chandra observations of 3CRR at z < 0.1, making the sample useful for statistical studies. Only Chandra can resolve the multiple components of these sources, as is needed for an improved understanding of source physics and gas heating. The imaging and spectroscopy of cores, jets, hot spots, and atmospheres will be of permanent legacy value. We will use the data to investigate particle acceleration, interactions between radio plasma and the ISM and IGM, the emission mechanisms of hot spots, and AGN fueling. Comparison with our complete Spitzer coverage and HST images will aid interpretation. The dataset will be made public immediately.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
18:38:26.30	+17:11:49.70	3C 386	ACIS-I	NONE	30
22:49:54.70	+11:36:30.10	NGC 7385	ACIS-I	NONE	40
03:58:54.40	+10:26:03.00	3C 98	ACIS-I	NONE	30
07:47:57.90	+55:45:46.30	DA 240 W	ACIS-I	NONE	25
07:49:15.90	+55:52:10.30	DA 240 E	ACIS-I	NONE	25
09:49:46.00	+73:14:23.10	4C 73.08	ACIS-I	NONE	30
01:12:02.20	+49:28:35.00	3C 35	ACIS-I	NONE	25
12:29:52.30	+11:40:38.90	1227+119	ACIS-I	NONE	30
15:52:09.20	+20:05:23.70	3C 326	ACIS-I	NONE	50
15:51:43.20	+20:04:17.70	3C 326 W	ACIS-I	NONE	35
10:05:24.20	+34:59:11.40	3C 236 W	ACIS-I	NONE	30
10:06:18.40	+34:51:56.40	3C 236 C	ACIS-I	NONE	40
10:07:12.60	+34:44:41.40	3C 236 E	ACIS-I	NONE	30

Subject Category: ACTIVE GALAXIES AND QUASARS

Proposal Number: 10700584

Title: Deconstructing AGN X-ray Spectra - Time for a Paradigm Shift?

PI Name: Tracey Turner

We aim to detect and measure the ionization state and outflow velocities in the well-studied low-BH-mass AGN NGC 4051. We have been granted a 340 ks Suzaku observation to study continuum and low-resolution line spectral variability; HETG spectroscopy complements this by isolating narrow absorption lines arising from key zones of gas, allowing us to measure ionization, column and outflow velocities of the multiple ionized zones. A moderately ionized zone in particular can mimic the appearance of a broad Fe emission line but can be revealed by 6.5 keV Fe Kalpha absorption, for which there is already tentative evidence. A 320 ks HETG exposure will provide powerful diagnostic signatures across a wide range of ionisation. We also request HST time for tie-in UV spectroscopy.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
12:03:09.60	+44:31:52.80	NGC 4051	ACIS-S	HETG	320

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 10800641

Title: A Deep Image of the Most Powerful Cluster AGN Outburst

PI Name: Brian McNamara

Powerful AGN outbursts in galaxy clusters can release upward of 1E61 erg into the intracluster medium. Events of this magnitude are able to quench cooling flows and drive large-scale outflows that redistribute and heat the gas on cluster-wide scales. The most potent example of this is seen in the z=0.22 cluster MS0735.6+7421, whose powerful shock and cavity system have injected an estimated 6E61 erg of energy into the ICM. We propose to obtain a 500 ksec ACIS image of the cluster to examine in detail the relationships between the shock, cavity, and radio systems, and to investigate the impact of powerful AGN outbursts on the structure of the cluster.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
07:41:44.00	+74:14:38.30	MS0735.6+7421	ACIS-S	NONE	500

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 10800762

Title: The Role of AGN in Massive Galaxy Formation

PI Name: Spencer Stanford

There is increasing evidence that high rates of star formation in massive galaxies was common in rich environments at z > 1. The leading candidate for quenching the star formation and transforming cluster galaxies into red sequence galaxies is AGN. Therefore we expect to see an increase in AGN incidence in dense environments at z > 1. We propose to systematically determine the incidence of AGN in galaxy clusters at 1 < z < 1.5 using moderately deep ACIS imaging of IR-selected clusters in the Bootes field. In conjunction with extensive data from Spitzer, HST, and Keck, we will test the AGN quenching paradigm for the origin of the stars in massive galaxies.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
14:29:14.30	+33:57:20.70	ISCS1051	ACIS-I	NONE	24
14:26:09.50	+34:03:41.10	ISCS1034	ACIS-I	NONE	12
14:32:29.20	+33:32:48.30	ISCS1017	ACIS-I	NONE	33
14:26:30.40	+33:39:33.20	ISCS1014	ACIS-I	NONE	35
14:29:18.50	+34:37:25.80	ISCS1030	ACIS-I	NONE	32
14:34:30.40	+34:27:12.30	ISCS1034	ACIS-I	NONE	35
14:32:38.40	+34:36:49.00	ISCS1029	ACIS-I	NONE	32
14:32:24.20	+32:50:03.70	ISCS1036+1088	ACIS-I	NONE	36
14:25:19.30	+34:28:38.20	ISCS0890	ACIS-I	NONE	36
14:34:46.30	+35:19:45.80	ISCS1025	ACIS-I	NONE	34

Subject Category: CLUSTERS OF GALAXIES

Proposal Number: 10800779

Title: Shocks, Ripples, and Bubbles: A Very Deep Observation of Abell 2052

PI Name: Elizabeth Blanton

The cooling flow cluster A2052 has, arguably, the morphology most similar to the Perseus cluster as seen with Chandra. Two clear bubbles to the N and S of the center of A2052 are filled with the radio lobes associated with 3C 317. Surface brightness discontinuities consistent with shocks with Mach numbers of 1.8 and 1.2 are seen near the cluster center. These may be isothermal shocks. We propose to observe Abell 2052 much more deeply to study these shock features, ripple features due to sound waves that may be found at larger radii, possible ghost bubbles, cooling gas in the bright shells around the radio source that may link the X-ray and H-alpha emission, and possible hot gas within the X-ray holes. We will directly compare the star formation and cooling rates in the cluster center.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
15:16:44.50	+07:01:16.60	Abell 2052	ACIS-S	NONE	500

Subject Category: EXTRAGALACTIC DIFFUSE EMISSION AND SURVEYS

Proposal Number: 10900836

Title: A Benchmark Observation of the Warm-Hot Intergalactic Medium

PI Name: Taotao Fang

Searching for the ``Missing baryons'', in the form of the warm-hot intergalactic medium (WHIM), is a fundamental challenge faced by the current theory of structure formation. Cosmological simulations predict that majority of the WHIM can be probed in X-ray only, yet the reported detections are often in question due to statistical and systematical issues. Based on the tentative evidence in our joint XMM-Chandra ToO observations of H 2356-309, we propose a deep, non-ToO Chandra observation to definitively detect the WHIM absorption line with a measured column density expected from theory. A null detection would place an upper limit which cannot be explained by current cosmological simulations, and put future pursuit of the WHIM with current generation of X-ray telescopes in question.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
23:59:07.90	-30:37:41.00	H 2356-309	HRC-S	LETG	500

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