Accepted Cycle 15 Observing Proposals

NORMAL GALAXIES DIFFUSE EMISSION & SURVEYS

Proposal Number	Subject Category	PI Name	Type	Time (ks)	Title
15610373	NORMAL GALAXIES: DIFFUSE EMISSION	Walker	GO	100	Detecting the hot gaseous halo around an extremely massive and relativistic jet launching spiral galaxy
15610450	NORMAL GALAXIES: DIFFUSE EMISSION	Bregman	GO	120	The Missing Baryons Around Early-Type Galaxies
15610544	NORMAL GALAXIES: DIFFUSE EMISSION	Bogdan	GO	170	Hot X-ray Coronae: A Unique Probe of Galaxy Formation Models
15610735	NORMAL GALAXIES: DIFFUSE EMISSION	Machacek	GO	240	A Study of Hydrodynamic Instabilities in the Major Merger of Galaxy Groups NGC7618 and UGC12491
15610786	NORMAL GALAXIES: DIFFUSE EMISSION	Irwin	GO	155	A First Look at Giant Bulge-Dominated Low-Surface Brightness Galaxies
15620082	NORMAL GALAXIES: X-RAY POPULATIONS	Thuan	GO	85	[NeV] Emission and Ultraluminous X-ray Sources in Two Low-metallicity Blue Compact Dwarf Galaxies
15620105	NORMAL GALAXIES: X-RAY POPULATIONS	Kaaret	GO	94.8	X-Rays from Lyman Break Analogs
15620465	NORMAL GALAXIES: X-RAY POPULATIONS	Hornschemeier	GO	75	0.5-30 KEV IMAGING OF STARBURSTS WITH CHANDRA AND NUSTAR
15620687	NORMAL GALAXIES: X-RAY POPULATIONS	Lin	GO	60	Chandra Observation of the Most Luminous Off-nuclear Intermediate-mass Black Hole Candidate
15620745	NORMAL GALAXIES: X-RAY POPULATIONS	Binder	GO	130	The Effect of Intermediate-Luminosity Transients on the X-ray Luminosity Functions of Spiral Disks
15620749	NORMAL GALAXIES: X-RAY POPULATIONS	Zepf	GO	75	Long-term X-ray and Optical Study of the Black Hole X-ray Binaries in the Elliptical Galaxy NGC 4472
15620805	NORMAL GALAXIES: X-RAY POPULATIONS	Lehmer	GO	112	TESTING THE UNIVERSALITY OF THE STELLAR IMF USING CHANDRA
15620853	NORMAL GALAXIES: X-RAY POPULATIONS	Haggard	LP	420	Monitoring the Tidal Disruption of the Gas Cloud G2 As It Encounters Sgr A*

Subject Category: NORMAL GALAXIES: DIFFUSE EMISSION

Proposal Number: 15610373

Title: Detecting the hot gaseous halo around an extremely massive and relativistic jet launching spiral galaxy

Type: GO Total Time (ks): 100

PI Name: Stephen Walker

Here we propose to observe the extremely massive, rapidly rotating, relativistic jet launching, spiral galaxy 2MASX J23453268-0449256 to detect its hot halo and measure its mass content. The optical data indicate there is a huge central concentration of mass, including a SMBH, but X-ray observations are needed to determine its mass. It is extremely rare for a massive spiral galaxy to eject relativistic jets, as they are nearly always launched from the nuclei of bulge dominated ellipticals and not flat spirals. It is clear that J2345-0449 is an extremely rare system whose properties challenge the standard paradigm for the formation of relativistic jets in AGN. Detailed X-ray observations are necessary to fully understand this system and complement the excellent GMRT and VLA radio data.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
23:45:32.60	-04:49:23.40	2MASX J23453268-0449256	ACIS-S	NONE	100

Subject Category: NORMAL GALAXIES: DIFFUSE EMISSION

Proposal Number: 15610450

Title: The Missing Baryons Around Early-Type Galaxies

Type: GO Total Time (ks): 120

PI Name: Joel Bregman

Based on their stellar and cool gas content, galaxies are missing most of their baryons, yet additional gas may lie in a hot multi-million degree halo stretching to the virial radius. Our ROSAT stacking analysis shows that the average galaxy possesses only a modest extended gas halo, but studies of two individual isolated elliptical galaxies indicate that such massive halos exist. To investigate this difference, we propose observations of two ellipticals with specially designed observations that minimize systematic uncertainties. The derived halo masses will show if the gas mass to dark matter ratio is nearly constant of if it varies greatly between galaxies. These gas masses and radial distributions are fundamental quantities, critical in constraining galaxy formation models.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
01:49:04.60	-14:58:29.00	NGC 682	ACIS-S	NONE	60
01:58:18.20	-54:12:57.00	ESO 153-G003	ACIS-S	NONE	60

Subject Category: NORMAL GALAXIES: DIFFUSE EMISSION

Proposal Number: 15610544

Title: Hot X-ray Coronae: A Unique Probe of Galaxy Formation Models

Type: GO Total Time (ks): 170

PI Name: Akos Bogdan

The presence of hot gaseous coronae in the dark matter halos of massive galaxies is a basic prediction of galaxy formation models, yet observations of such coronae are very scarce. We propose to test galaxy formation models by characterizing the outer hot coronae of two massive spiral galaxies. The selected galaxies are optically luminous, undisturbed, have low star formation rates, and can be probed to large radii within the Chandra field-of-view. We will measure the properties of the hot coronae, furthermore we will construct density, temperature, and abundance profiles. Confronting the observed properties of the coronae with those predicted by state-of-the art galaxy formation models, will allow us to probe fundamental physical processes that influence galaxy formation.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
00:49:47.80	+32:16:39.80	NGC266	ACIS-I	NONE	90

Subject Category: NORMAL GALAXIES: DIFFUSE EMISSION

Proposal Number: 15610735

Title: A Study of Hydrodynamic Instabilities in the Major Merger of Galaxy Groups NGC7618 and UGC12491

Type: GO Total Time (ks): 240

PI Name: Marie Machacek

NGC7618/UGC12491 is the best nearby examples of the merger of two equal mass galaxy groups. Their dramatically distorted X-ray cold fronts suggest the presence of Kelvin Helmholtz Instabilities (KHI). We propose 120 ks ACIS-S observations of NGC\,7618 and UGC\,12491 to measure the gas temperatures, metal abundances, densities, pressures and entropy in these distorted features to determine their origin and gas flow histories. We will measure the limiting observable size for KHI instabilities and improve constraints on effective gas viscosity along the cold front boundaries.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
23:19:47.20	+42:51:09.50	NGC7618	ACIS-S	NONE	120
23:18:38.30	+42:57:28.90	UGC12491	ACIS-S	NONE	120

Subject Category: NORMAL GALAXIES: DIFFUSE EMISSION

Proposal Number: 15610786

Title: A First Look at Giant Bulge-Dominated Low-Surface Brightness Galaxies

Type: GO Total Time (ks): 155

PI Name: Jimmy Irwin

Low surface brightness galaxies (LSBs) might appear optically unimpressive, but the largest LSBs contain as many stars as the largest normal elliptical and spiral galaxies. Next to nothing is known about their X-ray properties. We propose moderate length Chandra observations of three giant, bulge-dominated LSBs that cover over an order of magnitude in L_K to firmly detect for the first time the expected hot gaseous bulge emission from these systems, and compare their L_X/L_K scaling relation with normal early-type spiral bulges/ellipticals. We will also search for ULXs in the faint disks of these intriguing systems.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
02:27:45.90	+28:12:32.00	UGC 1922	ACIS-S	NONE	45

Subject Category: NORMAL GALAXIES: X-RAY POPULATIONS

Proposal Number: 15620082

Title: [NeV] Emission and Ultraluminous X-ray Sources in Two Low-metallicity Blue Compact Dwarf Galaxies

Type: GO Total Time (ks): 85

PI Name: Trinh Thuan

We propose to observe two extremely metal-poor Blue Compact Dwarf (BCD) galaxies, Tol 1214-277 and HS0837+4717, as nearby proxies for studying hard radiation at high z. These BCDs are remarkable due to their strong [Ne V] 3426 emission, i.e., ionizing radiation with E>100eV. We wish to verify directly with Chandra that each BCD contains an X-ray source with L(X)>~1e39 erg/s, as predicted by photoionization models. We expect modest yet robust detections which can highlight spectral extremes and XRB locations relative to [Ne V]. Null detections would provide strong constraints for ionization models. By enlarging the number of known BCDs with ULXs (7 to date) and ULX/[Ne V] detections (1), we will be able to investigate trends of L(X) with other BCD properties.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
12:17:17.10	-28:02:32.70	Tol1214-277	ACIS-S	NONE	30

Subject Category: NORMAL GALAXIES: X-RAY POPULATIONS

Proposal Number: 15620105

Title: X-Rays from Lyman Break Analogs

Type: GO Total Time (ks): 94.8

PI Name: Philip Kaaret

The source of energetic photons that reionized the early universe remains uncertain. Early galaxies had low metallicity and recent population synthesis calculations suggest that the number and luminosity of high-mass X-ray binaries is enhanced in star-forming galaxies with low metallicity, offering a potentially important and previously overlooked source of reionization. We propose to measure the relation between star formation rate and X-ray luminosity in a sample of Lyman break analogs, local galaxies that strongly resemble high-redshift, star-forming galaxies, and test the predicted enhancement in X-ray luminosity. These observations are important to our understanding of reionization and the formation of early galaxies.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
00:55:27.50	-00:21:48.60	SDSS J005527.46-002148.6	ACIS-S	NONE	23
08:46:02.20	+52:31:59.10	SDSS J084602.23+523159.1	ACIS-S	NONE	7.4
08:24:13.10	+43:37:21.00	SDSS J082413.13+433721.0	ACIS-S	NONE	23.7
09:38:13.50	+54:28:25.10	SDSS J093813.50+542825.1	ACIS-S	NONE	15.7
23:07:03.70	+01:13:11.20	SDSS J230703.75+011311.2	ACIS-S	NONE	25

Subject Category: NORMAL GALAXIES: X-RAY POPULATIONS

Proposal Number: 15620465

Title: 0.5-30 KEV IMAGING OF STARBURSTS WITH CHANDRA AND NUSTAR

Type: GO Total Time (ks): 75

PI Name: Ann Hornschemeier

We propose short 10-30 ks Chandra exposures of a sample of four starburst galaxies that will occur concurrently with priority A NuSTAR observations. With this 75 ks program, we will characterize binaries, ULX sources and accretion onto supermassive black holes. Such joint Chandra-NuSTAR observations were crucial to interpretation of the 0.5-30 keV emission from the nuclear region of NGC 253 in late 2012 (Lehmer et al. 2013). In this proposal, we seek to continue to leverage the combined power of the two facilities. The sample consists of the very nearby star-forming galaxies M82 and M83 at d=4 Mpc and the nearest two merging starburst galaxies, NGC 3310 and NGC 3256, which altogether will be observed by NuSTAR for 481 ks.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
09:55:52.20	+69:40:48.70	M82	ACIS-S	NONE	20
13:37:00.90	-29:51:56.70	M83	ACIS-I	NONE	30
10:38:45.90	+53:30:11.80	NGC 3310	ACIS-S	NONE	10
10:27:51.60	-43:54:18.00	NGC 3256	ACIS-S	NONE	15

Subject Category: NORMAL GALAXIES: X-RAY POPULATIONS

Proposal Number: 15620687

Title: Chandra Observation of the Most Luminous Off-nuclear Intermediate-mass Black Hole Candidate

Type: GO Total Time (ks): 60

PI Name: Dacheng Lin

Intermediate-mass black holes (IMBH, ~10^2-10^5 solar mass) have been long sought after as they are associated with several important astrophysical processes and in tight binaries could emit gravitational waves. The best IMBH candidates are hyperluminous off-nuclear X-ray sources (HLX) with L_X >10^41 erg/s, but very few are known. We have found a new HLX candidate L_X ~ 10^43 erg/s, with a possible optical counterpart, at 1'' from the host galaxy's centre. We require Chandra's supreme spatial resolution to confirm the off-nuclear nature and its association with the optical source. We recently proved that the host galaxy's central massive black hole is inactive, using Gemini spectra, making it very likely that our candidate is the most luminous off-nuclear IMBH known.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
14:17:11.00	+52:25:41.90	2XMM J141711.0+522541	ACIS-S	NONE	60

Subject Category: NORMAL GALAXIES: X-RAY POPULATIONS

Proposal Number: 15620745

Title: The Effect of Intermediate-Luminosity Transients on the X-ray Luminosity Functions of Spiral Disks

Type: GO Total Time (ks): 130

PI Name: Breanna Binder

We aim to measure the fraction of X-ray transients (XRT) and their luminosity distribution in NGC~300 using two new ACIS-I observations and joint HST ACS/WFC3 imaging. X-ray point source populations are characterized by their X-ray luminosity functions (XLFs), which are typically constructed from a single ``snapshot'' exposure. Most XLFs do not extend below of 10^37 erg s^-1, and the consistency of the XLF on short timescales poorly constrained. The two new exposures of NGC~300 will be used to address two broad science goals: we will measure the XRT demographics in NGC~300 and investigate their impact on the XLF down to 5x10^35 erg s^-1, and we will co-add all observations to measure the XLF down to 10^35 erg s^-1. We will identify new faint X-ray sources and test HMXB evolution models.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
00:54:53.50	-37:41:04.00	NGC 300	ACIS-I	NONE	130

Subject Category: NORMAL GALAXIES: X-RAY POPULATIONS

Proposal Number: 15620749

Title: Long-term X-ray and Optical Study of the Black Hole X-ray Binaries in the Elliptical Galaxy NGC 4472

Type: GO Total Time (ks): 75

PI Name: Steve Zepf

We propose to observe the Virgo elliptical NGC 4472 and its black hole binaries with Chandra for 25 ks once in each of the next three cycles. We also propose to obtain Gemini spectroscopy of the optical emission line from the black hole source RZ2109 over this same time interval. These data will be used to - 1) track the X-ray variability of RZ2109, 2) compare this variability seen in X-rays to that seen in the optical [OIII]5007 emission line, in order to constrain the overall spatial scale of this emission and the nature of this back hole source, 3) test for variability of the second globular cluster black hole X-ray source CXOU 1229410+0757442, and 4) use the time domain information to search for the presence of any new black hole sources in this galaxy.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
12:29:39.90	+07:55:30.00	XMMUJ122939.9 +075333	ACIS-S	NONE	75

Subject Category: NORMAL GALAXIES: X-RAY POPULATIONS

Proposal Number: 15620805

Title: TESTING THE UNIVERSALITY OF THE STELLAR IMF USING CHANDRA

Type: GO Total Time (ks): 112

PI Name: Bret Lehmer

We propose to conduct moderately-deep Chandra observations of six relatively low-mass elliptical galaxies (sigma < 100 km/s; LK ~ 10^10 LK,sol) to identify bright LMXBs in these systems. We will test recent claims that the IMFs of massive ellipticals, which have been well observed by Chandra, are bottom heavy and contain a factor of 3-4 times fewer LMXBs per unit stellar mass than the low-mass ellipticals studied here. The Chandra observations needed to study even bright LMXBs in low-mass ellipticals are almost nonexistent and inadequate for such a test. Our program will also provide first constraints on the emission from LMXB populations in these systems and its scaling with stellar mass, which can be compared with Chandra Deep Field stacking of similar ellipticals out to z ~ 0.8.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
12:23:34.90	+06:04:54.20	NGC 4339	ACIS-S	NONE	34
12:25:41.70	+12:48:37.30	NGC 4387	ACIS-S	NONE	37
12:35:30.60	+12:13:15.40	NGC 4550	ACIS-S	NONE	19
12:35:38.00	+12:15:50.40	NGC 4551	ACIS-S	NONE	22

Subject Category: NORMAL GALAXIES: X-RAY POPULATIONS

Proposal Number: 15620853

Title: Monitoring the Tidal Disruption of the Gas Cloud G2 As It Encounters Sgr A*

Type: LP Total Time (ks): 420

PI Name: Daryl Haggard

A dense, cold cloud (G2) is on a collision course with Sgr A*, the radio source at our Galactic Center. G2 is on an eccentric orbit and shows signs of tidal disruption by the black hole. High-energy emission from the Sgr A*/G2 encounter will likely peak at pericenter and continue over the next several years as the material circularizes. We propose 9 ACIS-S monitoring observations (5 simultaneous with VLA) to study the radiation properties of Sgr A* as G2 breaks up and feeds the accretion flow, to constrain the rates and emission mechanisms of faint X-ray flares, and to detect G2 itself as it is shocked and heated. Multiwavelength observations of this encounter will have a profound impact on our understanding of inefficient accretion flows into, and outflow from, massive black holes.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
17:45:40.00	-29:00:28.10	Sgr A*	ACIS-S	NONE	50
17:45:40.00	-29:00:28.10	Sgr A*	ACIS-S	NONE	50
17:45:40.00	-29:00:28.10	Sgr A*	ACIS-S	NONE	50
17:45:40.00	-29:00:28.10	Sgr A*	ACIS-S	NONE	50
17:45:40.00	-29:00:28.10	Sgr A*	ACIS-S	NONE	50
17:45:40.00	-29:00:28.10	Sgr A*	ACIS-S	NONE	40
17:45:40.00	-29:00:28.10	Sgr A*	ACIS-S	NONE	40
17:45:40.00	-29:00:28.10	Sgr A*	ACIS-S	NONE	40
17:45:40.00	-29:00:28.10	Sgr A*	ACIS-S	NONE	50

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