Accepted Cycle 13 Observing Proposals

STARS & WD

Proposal Number	Subject Category	PI Name	Title
13200007	STARS AND WD	Canizares	WN Stars in NGC 3603: the High Resolution Spectrum of HD 97950-C
13200020	STARS AND WD	Garmire	Revealing the Extent of the Cluster of Clusters in NGC 6357
13200041	STARS AND WD	Garmire	A Search for X-ray Emission from Colliding Magnetospheres in Young Eccentric Stellar Binaries (GTO part)
13200067	STARS AND WD	Garmire	A Chandra View of the RCW120 Bubble (GTO part)
13200167	STARS AND WD	Berger	Are Convective Dynamos Super-Saturated at High Rotation Velocities?
13200221	STARS AND WD	Micela	Simultaneous Chandra - CoRoT - Spitzer Observation of the Star Forming Region NGC 2264
13200236	STARS AND WD	Preibisch	Testing the scenario of triggered star formation at the periphery of the Carina Nebula: a Chandra study of NGC3324
13200257	STARS AND WD	Robrade	The X-ray puzzle of late B and early A stars
13200314	STARS AND WD	Leutenegger	A systematic measurement of the mass-loss rate of Zeta Ori
13200318	STARS AND WD	Rappaport	V1309 Sco: The First Directly Observed Merging Binary
13200342	STARS AND WD	Getman	A Chandra View of the RCW120 Bubble
13200394	STARS AND WD	Townsley	The Young 'Cluster of Clusters' NGC 6357: A Carina Complex in the Making?
13200439	STARS AND WD	Petit	Characterizing the X-ray Properties of Extreme Magnetic Massive Stars
13200441	STARS AND WD	Guenther	X-ray emission from beta Pic
13200445	STARS AND WD	Getman	A Search for X-ray Emission from Colliding Magnetospheres in Young Eccentric Stellar Binaries
13200481	STARS AND WD	Gagne	HETG Spectroscopy of WR 48a: a superluminous dusty Wolf-Rayet star
13200530	STARS AND WD	Ayres	Alpha Cen: Climbing out of a Coronal Recession?
13200630	STARS AND WD	Forbrich	Simultaneous X-ray and radio flaring of Young Stellar Objects in the Orion Nebula Cluster
13200633	STARS AND WD	Guinan	LIVING WITH A RED DWARF: MAGNETIC ACTIVITY, XUV IRRADIANCES OF dM STARS - EXOPLANET ATMOSPHERES AND ENVIRONMENT IMPACTS
13200652	STARS AND WD	Damiani	Star formation in the NGC7000/IC5070 complex
13200692	STARS AND WD	Saar	A Close Look At Middle-Aged Coronae: The Nearby 2.5 Gyr Old Cluster Ruprecht 147
13200788	STARS AND WD	Ness	Studies of the coronae of two K-dwarfs, 61 Cyg A and B
13200817	STARS AND WD	Grosso	ACIS-S observation of TWA 30AB, the second and third closest actively accreting and outflowing low-mass stars
13200819	STARS AND WD	Guerrero	Probing Shock-in Winds in the Central Star of the Planetary Nebula IC 4593
13200852	STARS AND WD	Ag eros	Deep Imaging of M37, A Better Hyades
13200853	STARS AND WD	Miller	Testing Star-Planet Interaction in Solar Analogs
13200857	STARS AND WD	Corcoran	Monitoring Dynamical Mass Loss from Eta Car with the HETG and STIS: The Rise to Maximum

Subject Category: STARS AND WD

Proposal Number: 13200007

Title: WN Stars in NGC 3603: the High Resolution Spectrum of HD 97950-C

PI Name: Claude Canizares

HD 97950-C is one of the young, high-mass Wolf-Rayet stellar powerhouses in the starburst young cluster of NGC 3603. In a modest 50 ks exposure with HETG, we can determine whether emission lines are broad or narrow in this effectively single WN6h star. The line width is a fundamental property of competing wind models for massive young stars. The proposed observation has the potential to provide our first definitive high-resolution spectrum of a WN star in a nearby starburst region. Given these results, we will be better positioned to pursue further observations on a firm basis for spectroscopic feasibility and to better interpret more distant starburst activity.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
11:15:07.20	-61:15:32.00	HD 97950 C	ACIS-S	HETG	50

Subject Category: STARS AND WD

Proposal Number: 13200020

Title: Revealing the Extent of the Cluster of Clusters in NGC 6357

PI Name: Gordon Garmire

This observation extends and enhances our Chandra/ACIS campaign on NGC 6357, a nearby massive star-forming complex that Chandra has revealed to be a ``cluster of clusters,'' perhaps a young analog to the Carina complex. We will study the massive stars and the high-luminosity tail of the pre-main sequence stellar population in G353.08+0.36 -- perhaps the youngest cluster in this complex, with an IR morphology reminiscent of the ``crevice'' HII region M17 -- and characterize diffuse X-rays tracing wind-shocked plasma and filling many of the complex overlapping bubbles that are carving up NGC 6357's natal giant molecular cloud.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
17:26:38.50	-34:34:23.80	G353.08+0.36	ACIS-I	NONE	60

Subject Category: STARS AND WD

Proposal Number: 13200041

Title: A Search for X-ray Emission from Colliding Magnetospheres in Young Eccentric Stellar Binaries (GTO part)

PI Name: Gordon Garmire

Among young binary stars whose magnetospheres are expected to collide near periastron, only the DQ Tau system has been observed near periastron in the X-ray band. A large X-ray flare, strongly attributed to the collision mechanism, was reported. We seek to confirm the discovery of this X-ray emission mechanism via a constrained GO proposal for periastron observations of four other young nearby binaries that have configurations similar to DQ Tau and have well-established orbital elements. We wish to propose, under the GTO program, unconstrained complementary observations of these targets away from periastron. These data will help us detect and characterize any enhanced emission seen at periastron, with the goal of identifying the best candidates for future multi-wavelength campaigns.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
16:22:46.80	-23:25:33.10	RXJ1622.7-2325_P1	ACIS-S	NONE	3
16:22:46.80	-23:25:33.10	RXJ1622.7-2325_P2	ACIS-S	NONE	3
04:32:43.00	+25:52:31.10	UZTauE_P1	ACIS-S	NONE	3
04:32:43.00	+25:52:31.10	UZTauE_P2	ACIS-S	NONE	3
05:30:42.60	-04:35:01.90	Parenago523_P1	ACIS-S	NONE	3
05:30:42.60	-04:35:01.90	Parenago523_P2	ACIS-S	NONE	3
16:54:44.80	-36:53:18.60	HD152404_P1	ACIS-S	NONE	3
16:54:44.80	-36:53:18.60	HD152404_P2	ACIS-S	NONE	3

Subject Category: STARS AND WD

Proposal Number: 13200067

Title: A Chandra View of the RCW120 Bubble (GTO part)

PI Name: Gordon Garmire

HII regions surrounded by shells of dense molecular gas (HII bubbles) are candidates for regions with triggered star formation. Current models of an HII expansion and triggering predict constrains on the parameter space in terms of radiation field and properties of a parental cloud. This in turn may be reflected in properties of underlying stellar population (USP). None of the nearby HII bubbles were observed in X-rays. We propose combined GTO+GO ACIS-I observation of the nearest to the Sun, the RCW120 bubble. Combined existing IR and X-ray data will allow to obtain clean and unbiased USP of RCW120 and compare its inferred properties with those of other star-forming regions. This has the potential to offer us a better understanding of the formation processes of stars in clusters.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
17:12:20.80	-38:29:30.50	RCW120	ACIS-I	NONE	30

Subject Category: STARS AND WD

Proposal Number: 13200167

Title: Are Convective Dynamos Super-Saturated at High Rotation Velocities?

PI Name: Edo Berger

The magnetic dynamo mechanism in fully convective ultracool dwarfs (>M6) is not understood. A key open question, and a direct test of proposed models, is whether the magnetic activity correlates with rotation. There are indications that X-ray activity may actually decrease in the fastest rotators, an effect termed super-saturation. However, in the current sample it is difficult to isolate this effect from the overall sharp drop in coronal X-ray emission beyond L0. Here we propose observations of ultracool dwarfs in the X-ray ``sweet-spot'' (M6-M9) with a wide range of rotation velocities (Rossby numbers). Establishing the existence of super-saturation will shed light on the nature of convective dynamos and potentially on centrifugal stripping of coronae.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
10:48:12.60	-11:20:08.20	GJ3622	ACIS-S	NONE	10
01:09:51.20	-03:43:26.40	LP647-13	ACIS-S	NONE	20
11:21:49.30	-13:13:08.40	2MUCD 10980	ACIS-S	NONE	20
11:55:42.90	-22:24:58.60	LP851-346	ACIS-S	NONE	20
15:21:01.00	+50:53:23.00	NLTT40026	ACIS-S	NONE	20
18:43:22.10	+40:40:21.00	GJ4073	ACIS-S	NONE	20
22:28:54.40	-13:25:17.90	GJ4281	ACIS-S	NONE	20

Subject Category: STARS AND WD

Proposal Number: 13200221

Title: Simultaneous Chandra - CoRoT - Spitzer Observation of the Star Forming Region NGC 2264

PI Name: Giuseppina Micela

We propose a 300 ks observation of the star forming region NGC2264, to be performed in December 2011, during a 30 day Spitzer and CoRoT joint observation of the region. The program, also involving a series of ground observations, will be a unique experiment: using three space telescopes we will, for the first time, monitor hundreds of young stellar objects simultaneously over a broad wavelength range. We will thus obtain crucial insights on the physics of flares, the morphology of coronal emitting structures, and the physical processes responsible for the extreme variability of Classical T Tauri Stars at all wavelengths.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
06:40:58.70	+09:34:14.00	NGC 2264	ACIS-I	NONE	300

Subject Category: STARS AND WD

Proposal Number: 13200236

Title: Testing the scenario of triggered star formation at the periphery of the Carina Nebula: a Chandra study of NGC3324

PI Name: Thomas Preibisch

We propose an ACIS observation of the poorly studied young cluster NGC3324 at the periphery of the Carina Nebula in order to reveal the stellar populations in the cluster and the surrounding clouds. Our Herschel maps suggest that the expanding bubbles driven by the massive stars in the Carina Nebula interact with the gas shell around NGC3324 and trigger star formation. Due to the huge field-star contamination, only X-ray images can identify the young stars in the area. In combination with the recent results from the Chandra Carina Complex Project for the inner parts of the Carina Nebula, the analysis of an X-ray selected sample of young stars in NGC3324 will provide information about the stellar ages and allow us to test the scenario of bubble interaction and triggered star formation.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
10:37:40.00	-58:41:30.00	NGC3324	ACIS-I	NONE	75

Subject Category: STARS AND WD

Proposal Number: 13200257

Title: The X-ray puzzle of late B and early A stars

PI Name: Jan Robrade

We propose Chandra observations of a sample of magnetic, chemically peculiar late B/early A stars to test them for intrinsic X-ray emission and its relation to the magnetically channelled wind shock (MCWS) model. We selected well studied, nearby Ap/Bp stars that are promising candidates for being X-ray sources, to study a possible dependence of the MCWS phenomenon on stellar mass/luminosity and to investigate X-ray generating mechanisms in intermediate mass stars in greater detail.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
04:06:36.40	+27:35:59.70	HD 25823	ACIS-S	NONE	12
03:36:17.40	-17:28:01.40	HD 22470	ACIS-S	NONE	11
04:32:37.50	-03:12:34.40	HD 28843	ACIS-S	NONE	11
05:59:43.30	+37:12:45.30	HD 40312	ACIS-S	NONE	10
14:23:02.20	-39:30:42.60	HD 125823	ACIS-S	NONE	10
18:56:40.50	-37:20:35.70	HD 175362	ACIS-S	NONE	11

Subject Category: STARS AND WD

Proposal Number: 13200314

Title: A systematic measurement of the mass-loss rate of Zeta Ori

PI Name: Maurice Leutenegger

We propose a 300 ks HETGS observation of the O supergiant Zeta Orionis. In combination with 74 ks archival data, we will make very high signal-to-noise measurements of emission line profile shapes, which sensitively measure the wind optical depth as a function of wavelength. We will use the wavelength dependence of wind optical depth from all usable lines to make a precise measurement of the mass-loss rate. The wavelength dependence of wind optical depth will also test the importance of porosity. We will use XCMFGEN, our powerful new radiative transfer code, to construct global models which will be fit to X-ray, UV, and optical data, providing the strongest possible constraints on stellar and wind properties.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
05:40:45.50	-01:56:33.20	Zeta Orionis	ACIS-S	HETG	300

Subject Category: STARS AND WD

Proposal Number: 13200318

Title: V1309 Sco: The First Directly Observed Merging Binary

PI Name: Saul Rappaport

Most stars are in binary systems, and it has long been accepted that, in some instances, binary interactions can lead to a merger. In the case of low-mass stars, it is believed that a class of rapidly rotating single giant stars (FK Com stars) descend from the mergers of contact binary systems (W UMa stars). The recent discovery of V1309 Sco, the first unambiguous real-time observation of a merging low-mass contact binary system, opens the exciting possibility of directly studying the first phases of evolution of a post-merger object. Our proposed Chandra observation is aimed at: establishing the suggested connection between W UMa and FK Com systems; studying, for the first time, the genesis of a rapidly rotating, active star; and placing constraints on current dynamo theories.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
17:57:32.90	-30:43:10.00	V1309 Sco	ACIS-S	NONE	35

Subject Category: STARS AND WD

Proposal Number: 13200342

Title: A Chandra View of the RCW120 Bubble

PI Name: Konstantin Getman

HII regions surrounded by dense molecular shells are candidates for the Collect & Collapse triggered star formation (C&C HII bubbles). Current models of an HII expansion and triggering predict constrains on the parameter space in terms of radiation field and properties of a parental cloud. This in turn may be reflected in properties of underlying stellar population. No case of probable C&C HII bubbles has yet been examined in X-rays. We propose GO+GTO ACIS-I observations of the nearest to the Sun, the RCW 120 bubble. Our joint X-ray/optical/IR/sub-mm study will give the best census yet obtained for a stellar population in a C&C HII bubble. Another important goal is to search for diffuse X-ray emission from shocked plasma that is expected to be confined in RCW 120 by its molecular shell.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
17:12:20.80	-38:29:30.50	RCW120	ACIS-I	NONE	50

Subject Category: STARS AND WD

Proposal Number: 13200394

Title: The Young 'Cluster of Clusters' NGC 6357: A Carina Complex in the Making?

PI Name: Leisa Townsley

We have discovered that the massive star-forming complex NGC 6357 is a "cluster of clusters" hosting several O3 stars, an embedded massive cluster just discovered by Chandra, and a 50-pc hot plasma outflow seen by ROSAT. NGC 6357 is perhaps a young analog of the Carina complex, which exhibits X-ray line emission possibly explained by charge exchange when hot plasma impacts and erodes its many cold molecular surfaces. NGC 6357 shows similar line emission, thus we propose 2 new ACIS-I pointings, sampling bright ROSAT emission at an edge-on ionization front and at the top of NGC 6357's proto-superbubble where the hot plasma appears to become unconfined. These new pointings contain no known stellar clusters, so the bright diffuse emission should show strong signatures of charge exchange.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
17:23:30.70	-34:21:10.50	G352.90+1.02	ACIS-I	NONE	40
17:23:06.90	-34:04:36.50	G353.08+1.24	ACIS-I	NONE	40

Subject Category: STARS AND WD

Proposal Number: 13200439

Title: Characterizing the X-ray Properties of Extreme Magnetic Massive Stars

PI Name: Veronique Petit

We propose to measure the X-ray characteristics of five magnetic massive stars. These stars are extreme in terms of their wind magnetic confinement and their rapid rotation rate. We will interpret these observations with our Rigid Field Hydrodynamics model and explore the effect of stellar parameters, surface magnetic field structures and wind parameters on the X-ray production. High-quality CCD spectra have been obtained for only a handful of early B stars with strong magnetic fields. The five proposed ACIS-S spectra will significantly increase the available sample with which to test the magnetically confined wind shock paradigm.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
15:53:55.90	-23:58:41.10	HR 5907	ACIS-S	NONE	25
07:53:03.60	-49:36:47.00	HR 3089	ACIS-S	NONE	15

Subject Category: STARS AND WD

Proposal Number: 13200441

Title: X-ray emission from beta Pic

PI Name: Hans Guenther

Mid A to mid B-type stars are expected to be X-ray dark, because they neither posses the convective envelopes of late-type stars, nor the strong winds of earlier stars. Still, some A stars show X-ray emission, but its production mechanism is a matter of debate. We propose to observe beta Pic (spectral type A5), one of the closest and best-studied A stars, with the HRC-I for 20 ks. An XMM-Newton pointing claims a detection, which is interpreted as very soft thermal emission, possibly from an accretion boundary layer. If true, beta Pic is the prototype of a new class of X-ray emitters, which should show up prominently in the softest X-rays probed by the HRC; if not the XMM-Newton data implies even more exotic scenarios such as charge-exchange in extra-solar comets.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
05:47:17.10	-51:03:59.40	beta Pic	HRC-I	NONE	20

Subject Category: STARS AND WD

Proposal Number: 13200445

Title: A Search for X-ray Emission from Colliding Magnetospheres in Young Eccentric Stellar Binaries

PI Name: Konstantin Getman

Among young binary stars whose magnetospheres are expected to collide near periastron, only the DQ Tau system has been observed near periastron in the X-ray band. A large X-ray flare, strongly attributed to the collision mechanism, was reported. We seek to determine whether colliding magnetospheres in young high-eccentricity binaries commonly produce X-ray flares, and to identify targets for future detailed multi-wavelength campaigns. We propose short Chandra GO observations of multiple periastron passages in three nearby young binaries, complemented by GTO observations of the systems away from periastron.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
16:22:46.80	-23:25:33.10	RXJ1622.7-2325_P1	ACIS-S	NONE	3
16:22:46.80	-23:25:33.10	RXJ1622.7-2325_P3	ACIS-S	NONE	3
04:32:43.00	+25:52:31.10	UZTauE_P1	ACIS-S	NONE	3
04:32:43.00	+25:52:31.10	UZTauE_P3	ACIS-S	NONE	3
05:30:42.60	-04:35:01.90	Parenago523_P1	ACIS-S	NONE	3
05:30:42.60	-04:35:01.90	Parenago523_P2	ACIS-S	NONE	3
05:30:42.60	-04:35:01.90	Parenago523_P3	ACIS-S	NONE	3
16:22:46.80	-23:25:33.10	RXJ1622.7-2325_P2	ACIS-S	NONE	3
04:32:43.00	+25:52:31.10	UZTauE_P2	ACIS-S	NONE	3

Subject Category: STARS AND WD

Proposal Number: 13200481

Title: HETG Spectroscopy of WR 48a: a superluminous dusty Wolf-Rayet star

PI Name: Marc Gagne

Chandra and XMM images of the G305 galactic star-forming region reveal a surprisingly bright X-ray source associated with the dusty WC8 binary WR 48a. The XMM-Newton PN spectrum of WR 48a is heavily absorbed with temperature components at 1 and 3 keV, the hotter component dominating the observed flux. WR 48a appears to be the most X-ray luminous Wolf-Rayet star known, after the WR+NS/BH binary Cyg X-3. Its Lx, comparable to the LBV binary eta Carinae, is >10 times higher than other WR+O binaries like WR 140. We propose to obtain HEG/MEG spectra of WR 48a to measure the width of the emission lines, determine abundances, and measure key H- and He-like diagnostics to assess the location and ionization timescale of the X-ray shocks.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
13:12:39.70	-62:42:55.80	WR 48a	ACIS-S	HETG	100

Subject Category: STARS AND WD

Proposal Number: 13200530

Title: Alpha Cen: Climbing out of a Coronal Recession?

PI Name: Thomas Ayres

Nearby Alpha Centauri contains the two best characterized G and K dwarfs, next to the Sun itself, thanks to the accurate orbit, resolved angular diameters, and well understood co-evolutionary state. Alpha Cen A & B also have the best studied stellar X-ray activity cycles, extending back to the 1970's. Present proposal is to continue tracking the evolving multi-decadal high-energy narrative of Alpha Cen with semiannual HRC-I pointings in Cycles 13-15, as solar twin A is expected to be rising to cycle maximum from an extended coronal recession. STIS E140M spectra will support and leverage the broad-band X-ray measurements by probing subcoronal dynamics and providing a low-T boundary condition for DEM modeling, with connection to HRC through the FUV Fe XII coronal forbidden line.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
14:39:29.80	-60:49:59.30	ALPHA CEN	HRC-I	NONE	60

Subject Category: STARS AND WD

Proposal Number: 13200630

Title: Simultaneous X-ray and radio flaring of Young Stellar Objects in the Orion Nebula Cluster

PI Name: Jan Forbrich

Both X-ray and radio data constrain high-energy processes in Young Stellar Objects. YSOs are known to show strong flares in both wavelength regimes, but the underlying connection is unclear. In the past, several attempts to simultaneously observe YSO variability at X-ray and radio wavelengths were successful only in very few cases. Mostly, the radio signal was too weak for appropriate time resolution. The EVLA now provides a fundamentally improved basis for such observations, offering a 14x increase in sensitivity compared to previous observations, while simultaneously providing spectral and full polarization information. To study flares, we propose to observe the Orion Nebula Cluster to obtain simultaneous X-ray and radio lightcurves for >50 YSOs on unprecedented timescales of minutes.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
05:35:16.70	-05:23:24.00	Orion Nebula Cluster	ACIS-I	NONE	86.4

Subject Category: STARS AND WD

Proposal Number: 13200633

Title: LIVING WITH A RED DWARF: MAGNETIC ACTIVITY, XUV IRRADIANCES OF dM STARS - EXOPLANET ATMOSPHERES AND ENVIRONMENT IMPACTS

PI Name: Edward Guinan

We propose to study the magnetic activity, dynamo structure, coronal plasma physics, and XUV spectral irradiances of dM stars with different rotations, ages, and vastly different levels of magnetic activity. The proposed Chandra ACIS-S spectrometry of nine dM stars with ages of ~1-12 Gyr will complement the Chandra/XMM archival data of predominantly younger, more active dM stars. This program will complete the parameter space of age, rotation and X-ray emission for dM stars. The X-ray data will also be combined with proposed/archival HST UV data. This study is part of our ongoing NSF-supported program to obtain XUV irradiances for G-M stars with different ages, and will have a major impact on studies of XUV radiation and its effects on the ionization of extrasolar planet atmospheres.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
04:42:55.80	+18:57:29.40	GJ 176	ACIS-S	NONE	5
13:30:02.80	-08:42:25.20	LHS 353	ACIS-S	NONE	10
19:20:33.50	-07:39:43.50	NSV 11919	ACIS-S	NONE	5
07:40:19.20	-17:24:45.00	LP 783-2	ACIS-S	NONE	5
08:20:04.30	+38:34:41.50	G 111-72	ACIS-S	NONE	30
04:31:11.50	+58:58:37.60	LHS 26	ACIS-S	NONE	5
20:56:48.50	-04:50:49.10	ROSS 193	ACIS-S	NONE	20
05:11:40.60	-45:01:06.20	GJ 191	ACIS-S	NONE	5
04:15:21.70	-07:39:17.30	40 Eri C	ACIS-S	NONE	5

Subject Category: STARS AND WD

Proposal Number: 13200652

Title: Star formation in the NGC7000/IC5070 complex

PI Name: Francesco Damiani

We propose a joint Chandra ACIS-I and XMM-Newton EPIC/pn observing program to discover the still unknown population of the star-forming region NGC7000/IC5070, at 600 pc. Recent Spitzer data have shown this region to host 2000 or more Young Stellar Objects of Classes 0 to II, but missed Class III stars, which are expected to be numerous as well. The requested combination of high-spatial resolution ACIS data (3 pointings, total exposure: 144 ks), and wider-field EPIC data (3 pointings, total exposure: 73.5 ks) optimizes coverage of both clustered and diffuse YSO populations. These data will permit studies of the star formation history, early cluster evolution, mass spectrum and segregation, with unprecedented accuracy for this rich region.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
20:57:57.00	+43:51:14.30	NGC7000 Pointing 1	ACIS-I	NONE	48
20:56:48.20	+43:44:53.40	NGC7000 Pointing 2	ACIS-I	NONE	48

Subject Category: STARS AND WD

Proposal Number: 13200692

Title: A Close Look At Middle-Aged Coronae: The Nearby 2.5 Gyr Old Cluster Ruprecht 147

PI Name: Steven Saar

Just six years ago Kharchenko (2005) used catalog data to identify Ruprecht 147 (R147) as the 15th closest stellar cluster to the Solar System. At a distance of only 250 pc, and an age estimated to be 2.5 Gyr, R147 is by far the closest old cluster: the next closest with an age > 1 Gyr is nearly twice as distant. We request a 240 ksec observation with ACIS-S near the cluster core to characterize the coronal emission in cool stars at an unexplored age: ~half solar. The data will close a large age gap in our understanding of coronal evolution, improve age-rotation-activity calibration and explore the coronal consequences of significant magnetic dynamo/activity changes which appear around this time.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
19:16:43.20	-16:12:17.60	Ruprecht 147	ACIS-S	NONE	250

Subject Category: STARS AND WD

Proposal Number: 13200788

Title: Studies of the coronae of two K-dwarfs, 61 Cyg A and B

PI Name: Jan-Uwe Ness

Observations of samples of stellar coronae are the only way to assess the physical connections between stellar parameters and coronal properties. Diversity in stellar parameters is an important goal, and we propose to fill the gap of early K dwarfs, adding two objects in one observation. 61Cyg is the nearest K dwarf binary, and the separation of 33" allows extraction of two separate grating spectra of each star. Grating spectra yield the best-possible characterization to date, unlikely to be beaten for several decades. The LETGS covers important low-ionization lines that are critical in such low-activity stars to cover the full temperature range. Also, 61Cyg B is the nearest late K dwarf yielding the smallest investment of exposure time for obtaining an LETGS spectrum.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
21:06:53.90	+38:44:57.90	61 Cyg	HRC-S	LETG	200

Subject Category: STARS AND WD

Proposal Number: 13200817

Title: ACIS-S observation of TWA 30AB, the second and third closest actively accreting and outflowing low-mass stars

PI Name: Nicolas Grosso

TWA 30AB is a remarkable young (7 Myr), late-type (M5+M4), and wide binary, recently identified in the TW Hya association. Located at a distance of only 42 pc to the Sun, TWA 30AB is the second and third closest actively accreting and outflowing low-mass stars. Both stars display strong [O iii] emission, which is extremely rare in Classical T Tauri stars and indicates collisional shock fronts from the jets. This imaging spectroscopy of TWA 30AB provides the unparalleled opportunity to probe with X-rays star-disk-jet interactions within 21 AU of two young low-mass stars, at a critical time in disk evolution and planet-building processes.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
11:32:18.20	-30:19:51.80	TWA 30A	ACIS-S	NONE	85

Subject Category: STARS AND WD

Proposal Number: 13200819

Title: Probing Shock-in Winds in the Central Star of the Planetary Nebula IC 4593

PI Name: Martin Guerrero

Shocks in the fast stellar winds of OB and WR stars are commonly detected in X-rays. Wind shocks may also account for the hard X-rays detected in some central stars of planetary nebulae (CSPNe), given the similarity to OB stars in Lx/Lbol, wind variability and super-ion signatures. The CSPN of IC 4593 displays noticeable wind variability, its low temperature cannot produce its super-ion UV lines and its distance and extinction are small, making it ideal to test the wind-shock production of hard X-rays in CSPNe. The observations will be used to assess whether super-ions in relatively cool CSPNe are associated with hard X-rays, to refine stellar atmosphere models, constraining clumping and mass-loss rates in CSPNe, and to investigate the spatial distribution of diffuse X-ray emission.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
16:11:44.50	+12:04:17.10	IC 4593	ACIS-S	NONE	80

Subject Category: STARS AND WD

Proposal Number: 13200852

Title: Deep Imaging of M37, A Better Hyades

PI Name: Marcel Ag eros

Recent studies suggest that the picture of stellar LX decaying from 10 Myr to 5 Gyr as a single power-law is overly simplistic. M37, a Hyades analog, has been carefully surveyed in the optical, and we propose complementary deep (450 ksec) ACIS-I imaging of this open cluster. M37's rich membership, good match to Chandra's FOV, and large number of measured periods (~700) make it ideal for examining the evolution of coronal X-ray emission. Together, our X-ray and optical data will provide independent determinations of LX and v_rot; map out M37's X-ray luminosity function, with stacking of optically similar sources extending our flux limits by ~10x; test whether magnetic effects produce anomalous optical colors/luminosities for high LX sources; and characterize M37's interacting binaries.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
05:52:18.80	+32:33:34.10	M37	ACIS-I	NONE	450

Subject Category: STARS AND WD

Proposal Number: 13200853

Title: Testing Star-Planet Interaction in Solar Analogs

PI Name: Brendan Miller

Simulations show close-in giant planets can influence stellar coronal activity (e.g, through magnetic interaction), but previous X-ray investigations (necessarily challenged by complex biases, or heavy censorship, or confounding variables) have produced ambiguous and contradictory results. We propose Chandra snapshot (5-15 ks) observations of 12 solar analogs with nearly identical stellar properties, hosting planets spanning msini=0.1-9.7 MJup and a=0.04-3.8 AU. We will test whether X-ray emission from stars with close-in planets is systematically enhanced, and evaluate or constrain the efficiency of any interaction. If star-planet interaction is indeed a ubiquitous phenomenon in ``hot Jupiter'' systems, X-ray enhancements may provide a unique direct probe of exoplanet magnetic fields.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
19:09:03.10	+34:35:59.50	HD 178911B	ACIS-S	NONE	10
18:21:49.80	-11:55:21.70	HD 168746	ACIS-S	NONE	10
06:51:30.50	+40:52:03.90	HD 49674	ACIS-S	NONE	12
01:04:40.20	-39:29:17.60	HD 6434	ACIS-S	NONE	9
04:26:26.30	-10:33:03.00	HD 28185	ACIS-S	NONE	9
12:19:13.50	-03:19:11.20	HD 107148	ACIS-S	NONE	10
15:13:28.70	-25:18:33.60	HD 134987	ACIS-S	NONE	5
19:52:04.50	+28:06:01.40	HD 188015	ACIS-S	NONE	13
21:28:12.20	-21:43:34.50	HD 204313	ACIS-S	NONE	10
19:46:58.10	+34:25:10.30	HD 187123	ACIS-S	NONE	10
11:44:50.50	-58:42:13.40	HD 102117	ACIS-S	NONE	7
04:41:54.40	-58:01:14.70	HD 30177	ACIS-S	NONE	15

Subject Category: STARS AND WD

Proposal Number: 13200857

Title: Monitoring Dynamical Mass Loss from Eta Car with the HETG and STIS: The Rise to Maximum

PI Name: Michael Corcoran

Eta Car is the nearest highly unstable extremely massive star and a key object for understanding how a star heads towards hypernova. Periodic minima in X-rays show it as an extremely eccentric binary with a massive companion. A surprising change in the X-ray emission during the January 2009 X-ray minimum might indicate a large-scale variation in the LBV primary's mass loss rate. We propose to obtain an HETGS observation of the system during AO13, at beginning of the X-ray increase which proceeds the minimum. We also request STIS mapping along with the HETGS observations to constrain the 3-D shape of the wind-wind interaction regions on scales of 1--1700AU from the star so as to test variable mass loss models

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
10:45:03.60	-59:41:04.30	Eta Car	ACIS-S	HETG	110

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