Accepted Cycle 11 Observing Proposals

STARS & WD

Proposal Number	Subject Category	PI Name	Title
11200015	STARS AND WD	Poppenhaeger	Star-Planet Interaction in the upsilon Andromedae extrasolar planet system
11200018	STARS AND WD	Canizares	X-Ray Spectroscopy of Nearby Young Stars in the TW Association
11200020	STARS AND WD	Predehl	The Chandra LETGS Soft X-ray Spectrum of the White Dwarf GD153
11200035	STARS AND WD	Garmire	Young Binary DQ Tau: The hunt for X-ray emission from colliding magnetospheres (GTO part)
11200062	STARS AND WD	Garmire	IC1396 HII region as a testbed of triggered star formation: BRC36 (GTO portion)
11200063	STARS AND WD	Ayres	The Ups and Downs of Alpha Centauri
11200069	STARS AND WD	Naze	Investigating HD148937, an enigmatic hot magnetic star
11200095	STARS AND WD	Preibisch	Revealing the ``missing' low-mass stars in the S255/S257 star forming region
11200153	STARS AND WD	Stelzer	X-ray emission from wide brown dwarf binaries
11200169	STARS AND WD	Oskinova	Cosmic archaeology with Chandra: from a supergiant shell to young stellar objects in NGC 602
11200179	STARS AND WD	Robrade	X-ray emission from the planet-bearing A-type star HR 8799 ?
11200199	STARS AND WD	Townsley	A New Story for Massive Star Formation in NGC 6357
11200214	STARS AND WD	Schmitt	The active host star of the extrasolar planet COROT-EXO-2b
11200217	STARS AND WD	Getman	BRC36/IC1396 as a Testbed of Triggered Star Formation (GO part)
11200232	STARS AND WD	Skinner	RY Tau: A T Tauri Star Driving a Spectacular Jet
11200236	STARS AND WD	Getman	Young Binary DQ Tau: The hunt for X-ray emission from colliding magnetospheres (GO part)
11200254	STARS AND WD	Povich	Uncharted Territory in M17: In Search of an Older Generation of Young Stars
11200282	STARS AND WD	Beiersdorfer	New LETGS Observations of Procyon
11200302	STARS AND WD	Osten	Magnetic Heating of the Outer Atmospheres of Very Low Mass Dwarfs
11200317	STARS AND WD	Rowell	Probing for multi-TeV particle acceleration towards W28-A2, a highly unusual ultra-compact HII region.
11200332	STARS AND WD	Guedel	NeII as a Tracer for X-Rays in Disks Around T Tauri Stars
11200378	STARS AND WD	Grosso	X-ray Census of Young Low-Mass Stars Candidates Associated with Gomez's Hamburger
11200418	STARS AND WD	Figer	The nature of GLIMPSE 81: a star cluster to rival Westerlund 1?
11200420	STARS AND WD	Guedel	New Thrust for Jets: Understanding the Physics of Young Stellar Jets and Outflows
11200435	STARS AND WD	Grady	The Stars and Edge-on Disks of PDS 144: An Intermediate-Mass Analog of Wide T Tauri Multiple Stars
11200492	STARS AND WD	Winston	A Chandra Snapshot of Serpens South
11200496	STARS AND WD	Guinan	Exploring a New Stellar X-ray Frontier: Investigating the X-ray Emissions of RR Lyr Variables
11200609	STARS AND WD	Robrade	X-ray emission from the fast rotating A7 star Altair
11200621	STARS AND WD	Schneider	Resolving the time-evolution of the HH 154 X-ray emission
11200668	STARS AND WD	Corcoran	Monitoring Dynamical Mass Loss from Eta Car with the HETG
11200698	STARS AND WD	Drake	The Chandra Cygnus OB2 Survey
11200702	STARS AND WD	Meibom	Rethinking the rotation-activity classifications of cool single and binary stars
11200754	STARS AND WD	BROWN	ACIS IMAGING SPECTROSCOPY OF T TAURI STARS IN THE HST/COS CYCLE 17 LARGE PROJECT SAMPLE
11200793	STARS AND WD	Testa	X-ray emission mechanism in the Be star HD 42054
11200837	STARS AND WD	Dupree	SLEUTHING THE MAGNETIC DYNAMO IN METAL-POOR STARS
11200899	STARS AND WD	Covey	Measuring X-ray Heating of Circumstellar Disks: Linking Stellar X-ray Flares With Mid-IR Disk Afterglows

Subject Category: STARS AND WD

Proposal Number: 11200015

Title: Star-Planet Interaction in the upsilon Andromedae extrasolar planet system

PI Name: Katja Poppenhaeger

We propose to carry out a 60 ks Chandra/ACIS-S observation of the planet bearing host star ups And to find coronal signatures of Star-Planet Interactions (SPI). ups And is one of the only two known stars with cyclically enhanced optical activity in phase with the planetary orbit. The proposed X-ray observation will establish SPI as a coronal effect, test if there are systematic differences between chromospheric and coronal planet-induced activity profiles and allow conclusions about the amount of energy deposited in the corona by SPI, about the planetary magnetic field and the planet's internal structure, its irradiation from the star and therefore its evaporation rate and lifetime.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
01:36:47.80	+41:24:19.80	HD 9826	ACIS-S	NONE	60

Subject Category: STARS AND WD

Proposal Number: 11200018

Title: X-Ray Spectroscopy of Nearby Young Stars in the TW Association

PI Name: Claude Canizares

To improve our understanding of X-ray emitting regions of T Tauri stars (TTS) we are conducting an X-ray spectroscopic study of the TW Hya Association (TWA). X-ray spectra of TWA stars provide plasma diagnostics that yield insights into the origin of X-ray emission from young stars and are diagnostic of accretion processes. The co-evolutionary population of 10 Myr-old TTS, their proximity, and their lack of X-ray absorbing cloud material make the TWA well suited to X-ray spectroscopy. Here, our focus is on a binary TTS system, TWA-19AB, the only TWA system known to include a G-star, important for determining the role of mass in pre-main-sequence X-ray emission. The close (40") K7 companion will provide an X-ray spectrum of a weakly accreting star similar to TW Hya itself.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
11:47:24.50	-49:53:03.00	TWA 19A	ACIS-S	HETG	60

Subject Category: STARS AND WD

Proposal Number: 11200020

Title: The Chandra LETGS Soft X-ray Spectrum of the White Dwarf GD153

PI Name: Peter Predehl

To calibrate X-ray instruments at low energies high resolution spectra of isolated white dwarfs are needed. So far only only HZ43 and Sirius B have been observed and studied in detail with the Chandra LETGS and EUVE. With this proposed Chandra LETGS observation and the existing EUVE data we will be able to further contrain the physical parameters the white dwarf GD153. Like this with the help of the three independant physical models for these white dwarfs we will be able to better calibrate low energy response (E<0.2keV) of existing and future X-ray detectors.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
12:57:02.30	+22:01:52.50	GD153	HRC-S	LETG	115

Subject Category: STARS AND WD

Proposal Number: 11200035

Title: Young Binary DQ Tau: The hunt for X-ray emission from colliding magnetospheres (GTO part)

PI Name: Gordon Garmire

The young high eccentricity binary DQ Tau exhibits powerful periodic mm flaring attributed to magnetosphere collisions of binary components. Simultaneous with mm CARMA, we propose combined GTO+GO Chandra ACIS-I3 observation of the periastron passage to search for X-ray emission from colliding magnetospheres. This proposal is a conditional GTO support of our GO-11 project (PI Getman) with similar title and object name.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
04:46:53.10	+17:00:00.10	DQ Tau	ACIS-I	NONE	30

Subject Category: STARS AND WD

Proposal Number: 11200062

Title: IC1396 HII region as a testbed of triggered star formation: BRC36 (GTO portion)

PI Name: Gordon Garmire

The formation of most stars in the Galaxy appears to be triggered by some external compression processes such as OB ionization, winds or supernovae. Quantitative understanding of triggering processes is still primitive. The radiation driven implosion (RDI) is the most observationally testable model using bright rimmed clouds (BRCs) on the edges of large HII regions. This 30 ksec ACIS-I GTO proposal is part of our program to map the IC1396 HII region in order to study contribution of RDI triggered stellar population to the total population of the region. This specific pointing is a GTO conditional support for our GO-11 project of similar title and object name (BRC36).

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
21:36:50.30	+57:30:24.00	IC1396_BRC36	ACIS-I	NONE	30

Subject Category: STARS AND WD

Proposal Number: 11200063

Title: The Ups and Downs of Alpha Centauri

PI Name: Thomas Ayres

Nearby Alpha Centauri hosts two of the best characterized late-type dwarfs, besides the Sun itself; thanks to the accurate orbit, resolved angular diameters, and well understood co-evolutionary state. The G and K components of the system have X-ray measurements extending back to the late-1970's; in some sense superior to the solar high-energy irradiance. The latter is not routinely measured in the normal cosmic energy bands, and must be reconstructed from proxies. The present proposal is to continue this ongoing twin coronal narrative with additional HRC-I pointings in Cycle 11, including an attempt to assess the importance of rotational modulation effects. FUV spectroscopy by HST-COS will leverage the unique coronal activity record.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
14:39:31.40	-60:50:01.00	Alpha Centauri	HRC-I	NONE	20

Subject Category: STARS AND WD

Proposal Number: 11200069

Title: Investigating HD148937, an enigmatic hot magnetic star

PI Name: Yael Naze

HD148937 is a peculiar magnetic hot star surrounded by a nebula thought to have been ejected by the star in an LBV-like event. It is one of the only three known Of?p objects of the Galaxy, and the X-ray brightest of its class. We propose to perform a detailed analysis of the high resolution X-ray spectrum of this star to pinpoint the exact origin of the X-ray emission in this peculiar class of objects.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
16:33:52.40	-48:06:40.50	HD148937	ACIS-S	HETG	100

Subject Category: STARS AND WD

Proposal Number: 11200095

Title: Revealing the ``missing' low-mass stars in the S255/S257 star forming region

PI Name: Thomas Preibisch

In the S255/S257 star forming region a dense cluster of young stellar objects is sandwiched between two HII regions. Interestingly, the exciting stars of the HII regions have no clusters of lower-mass stars around them, suggesting perhaps that these massive stars formed in isolation. If, however, these B0 stars are several Myr older than the embedded cluster, associated low-mass stars should be loosely scattered around them. Chandra is the ideal tool to uncover these young stars and to discern them from unrelated field stars by their strongly elevated X-ray emission. Chandra will provide a comprehensive census of young low-mass stars and reveal their spatial distribution, which will allow us to decide between the different proposed star formation scenarios for the S255/S257 region.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
06:12:54.00	+17:59:24.00	S255/S257	ACIS-I	NONE	75

Subject Category: STARS AND WD

Proposal Number: 11200153

Title: X-ray emission from wide brown dwarf binaries

PI Name: Beate Stelzer

Wide binary brown dwarfs offer a unique opportunity to study similarities and differences of substellar objects that were born and have evolved together. They also represent an efficient way to search for relations of brown dwarf X-ray emission with bolometric luminosity, effective temperature and mass, yielding two points in the parameter space at one shot. Only four wide binary brown dwarfs are known in various star forming regions. We have already successfully resolved one of them with Chandra, and propose here to observe all remaining three.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
04:23:35.40	+25:03:03.00	FU Tau	ACIS-S	NONE	60

Subject Category: STARS AND WD

Proposal Number: 11200169

Title: Cosmic archaeology with Chandra: from a supergiant shell to young stellar objects in NGC 602

PI Name: Lidia Oskinova

The Wing of the SMC has low metalicity, and low content of gas and dust. It provides an ideal nearby laboratory to study star formation and feedback in an environment that resembles the early Universe. We propose a 300 ks Chandra observation of NGC602, a massive star cluster at the edge of a supergiant shell in the Wing. This cluster has a simple morphology and is located in a region of high transparency for X-rays. The Chandra data will help to answer the fundamental questions about the mechanisms that sculpture the largest structures in the ISM, and trigger the formation of stars. This observation will be complemented with data from other NASA Great Observatories HST and Spitzer, and will establish a template for studies of active star formation in external galaxies.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
01:29:38.60	-73:34:25.10	NGC 602	ACIS-I	NONE	300

Subject Category: STARS AND WD

Proposal Number: 11200179

Title: X-ray emission from the planet-bearing A-type star HR 8799 ?

PI Name: Jan Robrade

We propose a 10 ks pointing with Chandra ACIS-S of the A5V star HR 8799. The star is associated with a RASS (ROSAT All Sky Survey) X-ray source, however its identification is uncertain. HR 8799 recently gained larger attention, when multiple orbiting planets were detected by direct imaging. With the proposed ACIS pointing we want to verify that the X-ray emission does indeed come from HR 8799 and investigate a potential future X-ray observation of this remarkable star.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
23:07:28.80	+21:08:02.90	HR 8799	ACIS-S	NONE	10

Subject Category: STARS AND WD

Proposal Number: 11200199

Title: A New Story for Massive Star Formation in NGC 6357

PI Name: Leisa Townsley

High-resolution X-ray observations of young massive stars and their surrounding clusters are yielding new insights into the star formation process. We request two 40-ks ACIS-I pointings in NGC 6357, a nearby massive star-forming complex comprised of a "cluster of clusters" that may be an OB association in the making. We will identify the source(s) of mysterious hard X-ray emission in component G353.2+0.7, study the massive stars and the high-luminosity tail of the pre-main sequence stellar population in the rich cluster in component G353.1+0.6, 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
17:25:34.20	-34:23:11.70	G353.1+0.6	ACIS-I	NONE	40
17:26:01.70	-34:15:15.40	G353.2+0.7	ACIS-I	NONE	40

Subject Category: STARS AND WD

Proposal Number: 11200214

Title: The active host star of the extrasolar planet COROT-EXO-2b

PI Name: Jurgen Schmitt

We propose to perform an exploratory X-ray pointing at the host star of the extrasolar planet COROT-EXO-2b. In contrast to almost all other extrasolar planet host stars, this star is remarkably active and (presumably) quite young. Its COROT light curve shows clear signatures of rotational modulation, and there is very pronounced structure in the transit light curves, which is explained by partial coverage of star spots by the COROT-EXO-2b planet. The presence of the planet thus acts as a sensitive shutter, sensing different parts of the stellar surface for inhomogeneities. The aim of this proposal is to determine the X-ray flux level of COROT-EXO2a, in order to assess the potential of follow-up X-ray studies.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
19:27:07.00	+01:23:02.00	2MASS J19270649+0123013	ACIS-S	NONE	15

Subject Category: STARS AND WD

Proposal Number: 11200217

Title: BRC36/IC1396 as a Testbed of Triggered Star Formation (GO part)

PI Name: Konstantin Getman

The formation of most stars in the Galaxy appears to be triggered by some external compression processes such as OB ionization, winds or supernovae. Quantitative understanding of triggering processes is still primitive. The radiation driven implosion (RDI) is the most observationally testable model using bright rimmed clouds (BRCs) on the edges of large HII regions. This combined GTO+GO Chandra ACIS-I proposal is part of our multi-wavelength program to map the IC1396 HII region in order to study contribution of RDI triggered stellar population to the total population of the region. This specific pointing is aimed at studying underlying stellar population of the famous BRC Elephant Trunk nebula.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
21:36:50.30	+57:30:24.00	IC1396_BRC36	ACIS-I	NONE	30

Subject Category: STARS AND WD

Proposal Number: 11200232

Title: RY Tau: A T Tauri Star Driving a Spectacular Jet

PI Name: Stephen Skinner

Jets have been discovered in a diverse range of astronomical objects (protostars, stars, galaxies, AGNs) and play an important role in the transport of mass, energy, and angular momentum. To date, the only example of a bipolar X-ray jet in a T Tauri star (TTS) is DG Tau. We propose here to observe RY Tau, which drives a similar bipolar jet but is a more luminous TTS and a brighter X-ray source. Chandra has the high angular resolution needed to search for jet X-ray emission close to the star and will provide information on jet morphology and physical conditions within the hottest regions of the jet. If the RY Tau jet emits at X-ray levels similar to that of DG Tau, it will be detected.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
04:21:57.40	+28:26:35.60	RY Tau	ACIS-S	NONE	60

Subject Category: STARS AND WD

Proposal Number: 11200236

Title: Young Binary DQ Tau: The hunt for X-ray emission from colliding magnetospheres (GO part)

PI Name: Konstantin Getman

The young high eccentricity binary DQ Tau exhibits powerful periodic mm flaring attributed to magnetosphere collisions of binary components. Simultaneous with mm CARMA, we propose combined GTO+GO Chandra ACIS-I3 observation of the periastron passage to search for X-ray emission from colliding magnetospheres. Properties of the discovered X-rays will be compared to those of the known X-rays at the orbital phase away from periastron. To give insights into the mechanism of X-ray production, morphology, energetics, magnetic field strengths, sizes of X-ray emitting coronal structures will be inferred and compared to those of the big COUP X-ray flares (Getman et al. 2008). This project has potential to offer us a different window to the origin of X-rays from young stars.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
04:46:53.10	+17:00:00.10	DQ Tau	ACIS-I	NONE	30

Subject Category: STARS AND WD

Proposal Number: 11200254

Title: Uncharted Territory in M17: In Search of an Older Generation of Young Stars

PI Name: Matthew Povich

We request a 40-ks ACIS-I pointing northeast of the giant H II region M17. M17 exhibits a unique, bright outflow of hot, wind-shocked plasma. It is located on the rim of a 20-pc diameter wind-blown bubble. This suggests that the young (~1 Myr old) massive NGC 6618 cluster ionizing M17 may have been triggered. We will search for the "trigger," a massive cluster called NGC 6618PG. While NGC 6618PG contains 7 OB stars, it lacks >1 Msun stars with disks, suggesting an age >2 Myr. It is impossible to separate cluster members from field stars using IR imaging alone. We require high-resolution X-ray imaging to address the following questions: Does the cluster exist? Does O star X-ray emission change significantly in a few Myr? What confines the hot plasma from M17 at its northern boundary?

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
18:21:11.30	-15:58:53.00	NGC 6618PG	ACIS-I	NONE	40

Subject Category: STARS AND WD

Proposal Number: 11200282

Title: New LETGS Observations of Procyon

PI Name: Peter Beiersdorfer

We propose a 140 ksec observation of Procyon with Chandra's LETGS to double the available data. LETGS observations of Procyon are the Rosetta Stone for understanding the emission in the 30-170 A band of cool stars and thus of their coronal physics. The existing LEGTS observations of Procyon have provided evaluations of the EMD, abundances, and the FIP effect based on a handful of lines from K-shell C, N, and O, M-shell Fe and Ni, and L-shell Si, S, and Mg lines. Other lines (e.g., FeXI, FeXII, FeXIII, FeXIV, FeXV, FeXVI), could not be used due to blending. We now can overcome this limitation, allowing us to study Procyon's coronal physics with much higher reliability, check for consistency with EUVE data, and provide critical input for the success of the Solar Dynamics Observatory.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
07:39:18.10	+05:13:30.00	Procyon	HRC-S	LETG	140

Subject Category: STARS AND WD

Proposal Number: 11200302

Title: Magnetic Heating of the Outer Atmospheres of Very Low Mass Dwarfs

PI Name: Rachel Osten

The detections of FUV and X-ray emissions from very low mass stars and brown dwarfs have confirmed that stellar magnetic activity can survive even at these low stellar masses. The emissions are qualitatively similar to those from active stars, despite the dramatic differences between the characteristics of It is currently an open question how the structures and magnetic heating which exists in these very low mass stars compare with those seen in higher mass active stars. We propose to take Chandra and HST/COS spectra of two nearby active very low mass stars in order to determine the effect that these large-scale fields have on transition region and coronal structures.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
14:56:38.30	-28:09:47.40	LHS 3003	ACIS-S	NONE	50
08:53:36.20	-03:29:32.10	LHS 2065	ACIS-S	NONE	40

Subject Category: STARS AND WD

Proposal Number: 11200317

Title: Probing for multi-TeV particle acceleration towards W28-A2, a highly unusual ultra-compact HII region.

PI Name: Gavin Rowell

The TeV gamma-ray sources in the field of the supernova remnant W28 present a unique opportunity to probe for a new type of multi-TeV particle accelerator - HII regions. Our proposal will observe the TeV source HESSJ1800-240B which is potentially linked to the highly unusual ultra-compact HII region W28A2. Our earlier XMM-Newton observations (badly affected by stray light) reveal point sources towards this region. With Chandra, we can study these X-ray sources in greater detail, and potentially resolve the arc-second scale ionisation ring and molecular outflows. These observations will provide new insight into the potential of very early stages of massive star formation to accelerate multi-TeV particles.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
18:00:27.00	-24:03:15.00	HESS J1800-240B (X-ray)	ACIS-I	NONE	80

Subject Category: STARS AND WD

Proposal Number: 11200332

Title: NeII as a Tracer for X-Rays in Disks Around T Tauri Stars

PI Name: Manuel Guedel

Although dust dominates the appearance of protoplanetary disks, the key processes for disk evolution, angular momentum and mass transport and planetesimal formation are driven through the dynamical state of the gas. In contrast to the dust component in disks, we do not have a similar knowledge of the gas component. One of the Spitzer breakthroughs was the detection of the [Ne II] line, proposed by Glassgold et al. (2007) to be a diagnostic for a warm disk surface layer that is heated and ionized by stellar X-rays. A correlation of the [Ne II] luminosity with the X-ray luminosity is expected. We aim at significantly enlarging the sample, specifically including targets with with transitional disks, low accretion and no jets or outflows.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
04:24:57.10	+27:11:56.30	IP Tau	ACIS-S	NONE	17.8
04:39:17.80	+22:21:03.50	LkCa 15	ACIS-S	NONE	10
04:41:16.80	+28:40:00.00	CoKu Tau/4	ACIS-S	NONE	10
04:30:04.00	+18:13:49.40	UX Tau A	ACIS-S	NONE	5.3
04:54:23.70	+17:09:53.50	St 34	ACIS-S	NONE	10
10:18:28.70	-31:50:02.90	TWA 6	ACIS-S	NONE	1.7
10:42:30.10	-33:40:16.20	TWA 7	ACIS-S	NONE	1.6
12:35:04.30	-41:36:38.60	TWA 10	ACIS-S	NONE	3.7
13:20:45.40	-46:11:37.70	TWA 17	ACIS-S	NONE	6.3

Subject Category: STARS AND WD

Proposal Number: 11200378

Title: X-ray Census of Young Low-Mass Stars Candidates Associated with Gomez's Hamburger

PI Name: Nicolas Grosso

Gomez's Hamburger is a bipolar nebula discovered in 1985 in front of the Galactic bulge that was believed to be a proto-planetary nebula, i.e., illuminated by a post-AGB star. This interpretation was recently challenged by millimetric observations that unveiled a spectacular CO disk in keplerian rotation around an intermediate-mass star. Gomez's Hamburger is a pre main-sequence intermediate-mass star with a circumstellar disk seen edge-on, located at about 300 pc. We propose a 17 ks observation with Chandra ACIS-I to select in X-rays the young low-mass star candidates associated with this object.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
18:09:13.30	-32:10:48.00	IRAS 18059-3211	ACIS-I	NONE	17

Subject Category: STARS AND WD

Proposal Number: 11200418

Title: The nature of GLIMPSE 81: a star cluster to rival Westerlund 1?

PI Name: Donald Figer

Young Massive Clusters (YMCs) are the ideal natural laboratory in which to probe the evolution of very massive stars through to supernova (SN) and beyond. We have identified one such cluster, GLIMPSE 81, which is rich in massive stars and which has been shown by XMM to emit hard X-rays. Here, we will use Chandra to resolve this emission and determine the relative contributions of massive binaries, post-SN objects (e.g. neutron stars), accreting relativistic binaries, and the diffuse emission of recent SNe. Ultimately, we will test the results from a similar study of Westerlund 1 that massive stars in clusters have binary fractions close to 100%. Further, we will use GLIMPSE 81 to provide links between massive stars and post-SN remnants, such as that of the nearby TeV source HESS~J1640.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
16:40:29.60	-46:23:25.80	GLIMPSE81	ACIS-I	NONE	40

Subject Category: STARS AND WD

Proposal Number: 11200420

Title: New Thrust for Jets: Understanding the Physics of Young Stellar Jets and Outflows

PI Name: Manuel Guedel

We propose a deep ACIS observation of the jet system of the classical T Tauri star DG Tau. DG Tau is so far unique because both its jet and counter-jet have been detected in X-rays. We will study jet structure, temperatures and proper motions of the sources and model the heating, propagation, and cooling physics of the hot plasma jets. The system orientation allows the counter-jet to be viewed through the circumstellar disk. X-ray absorption by the disk gas can thus be reliably determined and be used, together with optical information, to determine the gas-to-dust ratio in the disk. We will request radio (VLA) observations for complementary imaging, and near-IR (VLT) observing time for high-resolution spectroscopy to characterize the jet shocks and measure extinction along the jets.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
04:27:04.70	+26:06:16.20	DG Tau	ACIS-S	NONE	360

Subject Category: STARS AND WD

Proposal Number: 11200435

Title: The Stars and Edge-on Disks of PDS 144: An Intermediate-Mass Analog of Wide T Tauri Multiple Stars

PI Name: Carol Grady

High-Inclination PMS stars are optimally oriented to measure disk size, height, to detect jets, and to directly probe disk composition. Placing these data into evolutionary context requires dates for the systems and measurements of L_bol, and extinction. For such stars, X-ray data provide L_x, but also N(H) and the total extinction. FUV data measures L_UV, and constrains the shape of the extinction curve. Recent studies have suggested that the frequency of Jovian-mass planets is higher for systems with intermediate-mass stars, due to disk mass or composition. While suitable low mass YSOs are well-represented in the Chandra and HST archives, similar data are lacking for higher mass systems. We propose joint Chandra and HST imaging of PDS 144 to fill this gap.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
15:49:15.40	-26:00:52.50	PDS 144	ACIS-S	NONE	40

Subject Category: STARS AND WD

Proposal Number: 11200492

Title: A Chandra Snapshot of Serpens South

PI Name: Elaine Winston

We propose a 100ks observation of the recently discovered Serpens South, a densely populated, extremely young cluster. Our Spitzer data have identified 91 young stars in the region, 54 protostars and 37 Class II YSOs. This is one of the highest protostar fractions known in a YSC. Observations of the region with Chandra will allow us to identify the diskless Class III population of the cluster. They will also provide X-ray data of previously identified YSOs, allowing us to examine X-ray properties with evolutionary class and to study the spatial distribution of YSOs within the cluster. These observations will also compliment data from our Spitzer Warm Mission Program: YSOVAR, which will provide deep, multi-epoch mid-IR data of Serpens South.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
18:30:03.00	-02:01:58.20	Serpens South	ACIS-I	NONE	100

Subject Category: STARS AND WD

Proposal Number: 11200496

Title: Exploring a New Stellar X-ray Frontier: Investigating the X-ray Emissions of RR Lyr Variables

PI Name: Edward Guinan

Early theoretical predictions & spectroscopy suggest RR Lyr & Cepheids should be soft X-ray sources (pulsation-induced shocks). Yet no definite X-ray detections were made until the last 2 years when we discovered 3 Cepheids in X-rays (Lx ~ 10^29 ergs/s), likely caused by shock-heated plasmas. With shorter pulsation periods & more rapid atmospheric motions, RR Lyr should be stronger X-ray sources. In this pilot program we request a 50 ksec exposure (to cover the star's P ~13.5 hr pulsation period) to examine if RR Lyr variables join Cepheids as soft X-ray sources. We have selected the proto-type, RR Lyr itself, as the 1st target. These observations will shed new light on the structure, dynamics and heating of the atmospheres of this fundamentally important class of pulsating stars.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
19:25:27.90	+42:47:03.60	RR Lyr	ACIS-S	NONE	20

Subject Category: STARS AND WD

Proposal Number: 11200609

Title: X-ray emission from the fast rotating A7 star Altair

PI Name: Jan Robrade

We propose to observe the low activity star Altair with the Chandra LETGS. With a spectral type of A7, the very fast rotator Altair is the earliest, magnetically active, single late-type star detected by ROSAT and Einstein. Its X-ray luminosity is low and the activity level as expressed by the L_X/L_bol ratio is the lowest measured in any nearby star. Being located at a distance of only 5 pc, Altair is a unique target to study the X-ray properties of late A-type stars in greater detail. The proposed 100 ks observation will enable us to investigate the cool corona of a star with a very shallow convection zone in this spectral range. We expect to measure rotationally broadened stellar emission lines in the X-ray regime for the first time.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
19:50:47.30	+08:52:09.40	Altair	HRC-S	LETG	100

Subject Category: STARS AND WD

Proposal Number: 11200621

Title: Resolving the time-evolution of the HH 154 X-ray emission

PI Name: Christian Schneider

We propose to add to the available two Chandra images of HH 154 a new ACIS-S pointing of 70 ks to obtain a time-series with a baseline of nine years. The available data suggests two different X-ray emission components close to the heavily obscured driving source; one of these X-ray components might be associated with a knot in the HH-object while the nature of the seemingly stationary and more luminous component is still unclear. We want to clarify the structure of the X-ray emitting volume(s) to understand the physics of stellar outflows (e.g. collimation) and their interaction with the ambient medium (e.g. the role of turbulence). The new observation has the potential to solve pressing problems related to the production of X-rays within Herbig-Haro objects.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
04:31:34.10	+18:08:03.80	HH 154	ACIS-S	NONE	70

Subject Category: STARS AND WD

Proposal Number: 11200668

Title: Monitoring Dynamical Mass Loss from Eta Car with the HETG

PI Name: Michael Corcoran

Eta Car is a key object for understanding how mass and angular momentum change as a star heads towards hypernova. Periodic minima in X-rays and other wavebands 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 probably indicates a large-scale variation in the system mass loss which implies a significant change in the luminosity of one of the stars. X-ray line profiles are the best diagnostic of the wind-wind collision and the structure of the interacting winds. We propose to obtain HETGS spectra of the system during AO11 in a phase interval never before sampled, along with STIS mapping which will constrain the 3-D shape of the wind-wind interaction regions on scales of 1-1000AU.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
10:45:03.60	-59:41:04.30	Eta Car	ACIS-S	HETG	160

Subject Category: STARS AND WD

Proposal Number: 11200698

Title: The Chandra Cygnus OB2 Survey

PI Name: Jeremy Drake

Understanding massive "starburst" clusters is crucial for the first stars, starburst galaxies, galactic and ISM evolution, and star and planet formation on universal and galactic scales. But Galactic superclusters are generally too distant for detailed study. Recent awareness that Cygnus OB2 (1.5kpc; ~2Myr old) has supercluster characteristics has sparked a multiwavelength legacy effort exploiting its proximity to study starburst astrophysics. This Chandra Legacy project will provide an exquisite vision of the anatomy of a massive "collapse" mode of star formation, allowing detailed archeology of its history and content. 8000-10000 detections down to 0.1Msun will incisively test theories of giant molecular cloud collapse, massive star formation and protoplanetary disk evolution.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
20:33:12.00	+41:19:00.00	Cygnus OB2	ACIS-I	NONE	1080

Subject Category: STARS AND WD

Proposal Number: 11200702

Title: Rethinking the rotation-activity classifications of cool single and binary stars

PI Name: Soren Meibom

The traditional Rossby Number based classification of cool stars into normal, saturated, and supersaturated, bears some resemblance to the striking (C/g/I) sequences seen in carefully constructed color-period diagrams of open clusters - but there are significant differences. These differences could be clues to understanding the dynamo transitions of cool stars, and to understand whether binaries fit within the classification scheme. We propose here to explore the rotation-activity classifications of cool single and binary stars using Chandra ACIS-I spectra of coronae in the rich, nearby open cluster M35 (exceptionally well-studied for rotation periods, membership and binary orbits). We will explore how the coronal flux and temperature change across the various proposed classifications.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
06:09:10.00	+24:22:31.50	M35	ACIS-I	NONE	130

Subject Category: STARS AND WD

Proposal Number: 11200754

Title: ACIS IMAGING SPECTROSCOPY OF T TAURI STARS IN THE HST/COS CYCLE 17 LARGE PROJECT SAMPLE

PI Name: ALEXANDER BROWN

High energy (X-ray+UV) radiation from young stars profoundly influences physical and chemical processes in their circumstellar environment. Gas and dust in protoplanetary systems are excited by these photons, which are the dominant ionization source for hundreds of AU around the star. X-rays penetrate deep into disks and power complex chemistry on grain surfaces. We have been awarded 111 HST orbits to conduct a Large Project to observe the UV spectra of a carefully chosen sample of 31 young stars with COS and STIS. Modeling the effects of their high energy radiation requires BOTH UV and X-ray spectra for this sample. We propose to use ACIS-S to obtain CCD-resolution spectra for the FIVE stars in this sample that currently have not been observed by either Chandra or XMM-Newton.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
04:21:55.70	+27:55:06.20	DE Tau	ACIS-S	NONE	20
04:16:28.10	+28:07:35.70	LkCa 4	ACIS-S	NONE	20

Subject Category: STARS AND WD

Proposal Number: 11200793

Title: X-ray emission mechanism in the Be star HD 42054

PI Name: Paola Testa

We propose to obtain a HETGS spectrum of the Be star HD 42054 to investigate the X-ray emission mechanisms in this mid B-type emission line star characterized by hot and variable X-ray thermal emission. This study, through detailed line-based diagnostics accessible only with high resolution spectroscopy, will allow us to shed light into the issue of X-ray emission from Be stars. Remarkably, beta Cephei is the only Be star to date for which high-resolution X-ray spectra have been obtained, excluding the very peculiar class of gamma Cas analogs.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
06:07:03.70	-34:18:43.30	HD 42054	ACIS-S	HETG	150

Subject Category: STARS AND WD

Proposal Number: 11200837

Title: SLEUTHING THE MAGNETIC DYNAMO IN METAL-POOR STARS

PI Name: Andrea Dupree

Metal-poor stars on the red horizontal branch (RHB) have convective cores and semi-convective envelopes allowing for dynamo activity. The strong infrared He I line (10830A) we have detected in RHB field objects suggests also that X-ray emission is present to create the surprisingly strong helium absorption, yet no X-ray observations exist of this category of star. Discovery of X-rays from RHB objects will demonstrate for the first time that magnetic fields are present in normal Population II stars, provide a driving mechanism for the stellar winds indicated by line profiles, and have implications for globular clusters too, with respect to the 2nd parameter problem, and missing intracluster material.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
13:43:26.70	+15:34:31.00	HD 119516	ACIS-S	NONE	15

Subject Category: STARS AND WD

Proposal Number: 11200899

Title: Measuring X-ray Heating of Circumstellar Disks: Linking Stellar X-ray Flares With Mid-IR Disk Afterglows

PI Name: Kevin Covey

We propose to obtain Chandra ACIS-I observations of two young clusters, IC1396A and Ceph C, to test theoretical predictions of X-ray heating in circumstellar disks. Leveraging this Chandra data with extensive mid-IR light curves from our Spitzer Warm Mission program (YSOVAR), we will: 1) test if YSO X-ray and mid-IR variability are statistically correlated, indicating that stellar X-ray emission heats disks significantly, and 2) test if disk accretion rates rise following stellar X-ray flares, as expected from disk accretion models driven by magneto-rotational instabilities. Ancillary science includes: A) identification of weak T Tauri stars, to study their mid-IR variability; B) cluster extinction measurements; and C) LX/rotation relations with mid-IR periods for embedded protostars.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
23:05:51.00	+62:30:55.00	Ceph C	ACIS-I	NONE	48

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