Accepted Cycle 15 Observing Proposals

STARS & WD

Proposal Number	Subject Category	PI Name	Type	Time (ks)	Title
15200114	STARS AND WD	Mauerhan	GO	12	CHANDRA X-RAY OBSERVATIONS OF THE ETA CAR ANALOG NAST1 (WR 122): IS IT A COLLIDING-WIND BINARY?
15200163	STARS AND WD	Beiersdorfer	GO	95	High-Resolution Observations of Procyon's Fe L-shell Soft X-ray Emission
15200243	STARS AND WD	Green	GO	104.6	Rejuvenation of the Innocent Bystander: Testing Spin-Up in Dwarf Carbon Stars
15200307	STARS AND WD	Pooley	TOO	50	Catching an FUor in the Act: Chandra ToO Observations of Extreme Accretion onto Young Stars
15200333	STARS AND WD	Torrejon	GO	80	The eye of the hurricane. Exploring the innermost wind region of the massive star QV Nor.
15200353	STARS AND WD	Stelzer	GO	50	X-rays from the most nearby brown dwarf, WISE1049-5319
15200426	STARS AND WD	Schulz	GO	135	Wind Properties in a Very Young Pup
15200435	STARS AND WD	Salz	GO	60	X-ray irradiation of planets with atmospheres amenable to comprehensive follow-up
15200448	STARS AND WD	Guenther	GO	10	Can X-rays clear a circumstellar disk in 2 years?
15200476	STARS AND WD	Sahai	GO	70	INVESTIGATING BINARITY AND ACTIVE ACCRETION IN A NEW CLASS OF AGB STARS WITH FUV EXCESSES
15200512	STARS AND WD	Poppenhaeger	GO	141	Do exoplanets spin up their host stars?
15200514	STARS AND WD	SKINNER	GO	120	Coronal and Shock Emission in the Accreting T Tauri Star RY Tau
15200523	STARS AND WD	Kuhn	GO	40	Investigating Star-Formation in the Filaments and Bubble of IC 5146
15200539	STARS AND WD	Brown	GO	140	Measuring the X-ray Emission Impacting the Planets Orbiting Nearby Low-mass Stars
15200550	STARS AND WD	Melis	GO	25	X-ray Emission from a Radio-Loud Hyperactive L Dwarf
15200565	STARS AND WD	Brickhouse	LP	600	Accretion-Driven Physics on the Young Star BP Tauri
15200579	STARS AND WD	Wolk	GO	30	A Snapshot Survey of the Most Active Hot Jupiter Systems.
15200608	STARS AND WD	Petit	GO	125	Testing the wind-shock paradigm for B-type star X-ray production with theta Carinae (B0.2V)
15200662	STARS AND WD	Hamaguchi	GO	160	Probing the wind/radiative interactions with the circumstellar material at Periastron Passage of Eta Carinae
15200684	STARS AND WD	Kashyap	GO	25	X-Raying the Scorpion's Heart

Subject Category: STARS AND WD

Proposal Number: 15200114

Title: CHANDRA X-RAY OBSERVATIONS OF THE ETA CAR ANALOG NAST1 (WR 122): IS IT A COLLIDING-WIND BINARY?

Type: GO Total Time (ks): 12

PI Name: Jon Mauerhan

We propose Chandra ACIS observations of NaSt1 (aka WR 122). NaSt1 is the only candidate analog to the famous colliding-wind X-ray binary Eta Carina. It is an evolved, luminous, hot star that, like Eta Car, is embedded in a dense CNO-processed outflow. We have already secured HST observations of NaSt1 to determine the precise morphology of its nebula. Now, we require high-resolution X-ray imaging observations with Chandra/ACIS to determine if, like Eta Car, NaSt1 is an X-ray source, and moreover, a colliding-wind binary. The combined HST and Chandra data will reveal whether NaSt1 is truly an Eta Car analog, or something entirely different.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
18:52:17.40	+00:59:44.00	WR 122	ACIS-I	NONE	12

Subject Category: STARS AND WD

Proposal Number: 15200163

Title: High-Resolution Observations of Procyon's Fe L-shell Soft X-ray Emission

Type: GO Total Time (ks): 95

PI Name: Peter Beiersdorfer

We propose a 95 ksec observation of Procyon with the HETGS, which will provide the first high-resolution stellar observation of the L-shell emission lines of the M-shell Fe ions, which have been observed before only as absorption features in AGN spectra, such as the HETGS observation of NGC 3783. The temperature-sensitive ratio of the intensity of the Fe lines observed with the HETGS will be compared to the Fe lines observed with LETGS near 100 A to reevaluate a puzzling discrepancy between theory and observation noted in the spectra of Capella. The observation will also provide a temperature of Procyon's corona using a novel dielectronic satellite method and show that future missions require not only a high effective area but also high spectral resolution to use this method.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
07:39:18.10	+05:13:30.00	Procyon	ACIS-S	HETG	95

Subject Category: STARS AND WD

Proposal Number: 15200243

Title: Rejuvenation of the Innocent Bystander: Testing Spin-Up in Dwarf Carbon Stars

Type: GO Total Time (ks): 104.6

PI Name: Paul Green

Carbon stars (C>O) were long assumed to all be giants, because only AGB stars dredge up significant carbon into their atmospheres. We now know that dwarf carbon (dC) stars are actually far more common than C giants. These dCs are hypothesized to have accreted C-rich envelope material from an AGB companion, in systems that have likely undergone a planetary nebula phase, eventually yielding a white dwarf and a dC that has gained both significant mass and angular momentum. To test whether the X-ray emission strength and spectral properties are consistent with a rejuvenated dynamo, we propose a Chandra pilot study of dCs selected from the SDSS; some have hot white dwarf companions (indicating more recent mass transfer), and all show Balmer emission lines (a sign of activity).

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
10:15:48.90	+09:46:49.80	SDSS J101548.90+094649.7	ACIS-S	NONE	16.1

Subject Category: STARS AND WD

Proposal Number: 15200307

Title: Catching an FUor in the Act: Chandra ToO Observations of Extreme Accretion onto Young Stars

Type: TOO Total Time (ks): 50

PI Name: David Pooley

FU Orionis (FUor) outbursts are a transitory rapid accretion phase in the evolution of young stellar objects. We propose to obtain an X-ray spectrum during the rise to peak brightness of an FUor with Chandra. This phase has never been observed in X-rays and could reveal important information about the nature and source of the X-ray emission in these objects. In particular, it would provide a unique test of whether high-velocity jets are formed during the intense accretion event. These jets are expected to form X-ray dissociation regions, and X-ray emission does correlate with outflows from young stellar objects. If these jets only exist during the high levels of accretion during the rise to peak brightness, as they are thought to, X-ray observations during this time are crucial.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
		FUor Outburst	ACIS-S	NONE	50

Subject Category: STARS AND WD

Proposal Number: 15200333

Title: The eye of the hurricane. Exploring the innermost wind region of the massive star QV Nor.

Type: GO Total Time (ks): 80

PI Name: Jose Torrejon

We propose to use the unique high resolution capabilities of Chandra gratings to study in depth the stellar wind structure and properties of QV Nor, the B0I supergiant companion of the wind accreting pulsar 4U1538-52. The goal is to put observational constrains on the current models of stellar winds in massive stars using the point like source of ionizing X-rays as a probe. In particular we want to: a) characterize the rich emission line spectrum suggested by XMM, obtaining the first high resolution spectrum ever for this source. b) study the ionized wind of QV Nor in the innermost region r< 1.5R* which, to date, remains largely unexplored, c) finally, study the interstellar medium and the poorly known distance towards QV Nor by analyzing the properties of the dust scattered halo.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
15:42:23.40	-52:23:09.60	QV Nor	ACIS-S	HETG	80

Subject Category: STARS AND WD

Proposal Number: 15200353

Title: X-rays from the most nearby brown dwarf, WISE1049-5319

Type: GO Total Time (ks): 50

PI Name: Beate Stelzer

The magnetic activity of ultracool dwarfs, beyond the M/L spectral type transition, is nearly unconstrained as a consequence of the sensitivity limits of present-day instrumentation. To date only one L dwarf, Kelu1, has been detected at X-rays. The very recent discovery of WISE1049-5319, a brown dwarf binary at only 2pc from the Sun and the third-closest neighbor of the Sun, presents the opportunity to perform the deepest possible X-ray observations for an ultracool dwarf. A 50ksec Chandra observation allows us to move even beyond the sensitivity limits achieved for the (X-ray) brighter M dwarfs. The X-ray detection of WISE1049-5319 would represent a major step in our knowledge of magnetic activity in the substellar regime. A strong constraint on the upper limit would also be important.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
10:49:15.50	-53:19:06.10	WISE1049-5319	ACIS-S	NONE	50

Subject Category: STARS AND WD

Proposal Number: 15200426

Title: Wind Properties in a Very Young Pup

Type: GO Total Time (ks): 135

PI Name: Norbert Schulz

We propose HETGS observations of the central young IR star IRS2 in RCW 38 for 135 ks in order to obtain a high precision X-ray spectrum of a young (< 1.0 Myr) massive Zero Age Main- Sequence (ZAMS) star of very early O-type. In a first snapshot observation during Cycle 10 we were able to successfully rule out a contribution from an unseen low-mass companion and as well as significant contributions of magnetic activity. In this second part we provide enough exposure to determine detailed line properties and test for the presence of a thick wind, directly compare these properties to its mature cousin Pup, and investigate dynamic properties.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
08:59:05.60	-47:30:40.90	RCW38/IRS2	ACIS-S	HETG	135

Subject Category: STARS AND WD

Proposal Number: 15200435

Title: X-ray irradiation of planets with atmospheres amenable to comprehensive follow-up

Type: GO Total Time (ks): 60

PI Name: Michael Salz

We propose to measure the X-ray emission in a sample of six exoplanetary systems harboring Jovian planets with atmospheres amenable to comprehensive follow-up studies. Intense stellar high-energy irradiation on planetary atmospheres is thought to cause atmospheric heating, expansion and mass loss. To put models of irradiated atmospheres to a test, measurements of the X-ray and EUV emission are required for a large sample of planets. We identified planets with atmospheres that have the potential to be studied using time-resolved transit spectroscopy at UV and optical wavelengths. The proposed X-ray measurements will allow us to characterize the activity of the host stars, derive an estimate for the planetary mass-loss rate, and identify the most promising targets for follow-up studies.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
16:20:36.30	+41:02:53.10	HAT-P-2	ACIS-S	NONE	10
16:15:50.40	+10:01:57.30	Wasp-38	ACIS-S	NONE	10
02:28:37.20	-07:03:38.40	Wasp-77	ACIS-S	NONE	10
23:15:58.30	+31:27:46.30	Wasp-10	ACIS-S	NONE	10
23:59:36.10	-35:01:52.90	Wasp-8	ACIS-S	NONE	10
07:27:39.90	+24:20:11.40	Hat-P-20	ACIS-S	NONE	10

Subject Category: STARS AND WD

Proposal Number: 15200448

Title: Can X-rays clear a circumstellar disk in 2 years?

Type: GO Total Time (ks): 10

PI Name: Hans Guenther

Young stars are born surrounded by primordial disks. Eventually, these proto-planetary disks vanish. Some systems later form a debris disk with small dust grains. Up until May 2008 our target TYC 8241 2652 1 showed strong IR emission from such a disk. Between 2008 and 2010 the IR emission dropped by two orders of magnitude, which means that the dust mass in the inner disk decreased by 90-99%. The cause is unknown, but several hypotheses require high X-ray activity. We propose to observe this target for 10 ks with ACIS-S. This pointing will verify the association of a close-by ROSAT and XMM-Newton slew survey source with TYC 8241 2652 1, confirm the X-ray flux and look for signatures of high X-ray activity such as high plasma temperatures and Ne/Fe abundance ratios.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
12:09:02.20	-51:20:40.80	TYC 8241 2652 1	ACIS-S	NONE	10

Subject Category: STARS AND WD

Proposal Number: 15200476

Title: INVESTIGATING BINARITY AND ACTIVE ACCRETION IN A NEW CLASS OF AGB STARS WITH FUV EXCESSES

Type: GO Total Time (ks): 70

PI Name: Raghvendra Sahai

We propose a pilot survey for X-ray emission from AGB stars that are candidates for having binary companions with active accretion. These objects were identified via our innovative technique to search for FUV/NUV excesses in AGB stars using GALEX. The detection (or non-detection) of X-rays from this sample will enable us to begin testing models for the origin of the UV-excesses, leading to vital breakthroughs in our understanding of accretion-related phenomena and binarity in AGB stars. A larger survey, optimised using results fron this study, will be proposed in future cycles.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
07:41:08.50	+20:25:44.30	Y Gem	ACIS-S	NONE	10
02:11:48.90	-71:29:02.60	CI Hyi	ACIS-S	NONE	10
10:51:37.30	-21:15:00.30	V Hya	ACIS-S	NONE	10
08:46:21.20	+01:37:56.00	EY Hya	ACIS-S	NONE	10

Subject Category: STARS AND WD

Proposal Number: 15200512

Title: Do exoplanets spin up their host stars?

Type: GO Total Time (ks): 141

PI Name: Katja Poppenhaeger

We have collected initial evidence that tidal interaction between a late-type star and its close-in, massive planet can lead to a spin-up of the host star. We propose to explore this further by studying a small sample of proper motion pairs in which one of the stars is orbited by a Hot Jupiter. We will determine if the activity-estimated age appears to be strongly different for the two stars, which would indicate a tidal spin up of the Hot Jupiter host star. We propose to observe 4 such systems with Chandra/ACIS-S, and to perform a similar observation of one additional system with large angular separation using XMM-Newton/EPIC. The total proposed exposure times are 141 ks (Chandra) and 38 ks (XMM).

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
05:59:49.60	-48:14:22.00	HD 41004	ACIS-S	NONE	46
06:33:12.70	+05:27:45.30	HD 46375	ACIS-S	NONE	10
12:37:16.40	-40:48:43.60	HD 109749	ACIS-S	NONE	28
19:37:11.70	+28:29:59.50	HD 185269	ACIS-S	NONE	57

Subject Category: STARS AND WD

Proposal Number: 15200514

Title: Coronal and Shock Emission in the Accreting T Tauri Star RY Tau

Type: GO Total Time (ks): 120

PI Name: Stephen SKINNER

We have detected the accreting jet-driving T Tauri star RY Tau as a bright X-ray source with ACIS-S. Its spectrum shows numerous emission lines including O VII and Ne IX that likely originate in an accretion shock or the shocked jet, as well as lines such as Ca XIX and Fe K that form in very hot coronal plasma. Fluorescent iron emission (6.4 keV) from cold nearby material has also been seen. We propose here to obtain a HETG grating spectrum of RY Tau. Numerous emission lines will be detected and used to determine physical conditions in the hot plasma. The HETG spectrum along with an XMM RGS spectrum that is more sensitive to cool plasma will allow us to distinguish between coronal and shock emission and develop a complete picture of the origin of the X-ray emission.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
04:21:57.40	+28:26:35.50	RYTau	ACIS-S	HETG	120

Subject Category: STARS AND WD

Proposal Number: 15200523

Title: Investigating Star-Formation in the Filaments and Bubble of IC 5146

Type: GO Total Time (ks): 40

PI Name: Michael Kuhn

High-resolution X-ray observations of star-forming regions provide information about the populations and spatial distributions of young stars inaccessible from optical and infrared data, in particular the disk-free members. We propose a 40-ks observation of the young stellar cluster ionizing the IC 5146 HII region. The cluster lies in a structurally simple, nearby bubble powered by a B-type star located at the end of a 30-pc long molecular filament. With a clean sample of young stars obtained from the X-ray/IR/optical analysis, we will investigate clustering and spatial gradients in stellar ages and disk fractions to learn about the region's morphology and history. In addition, we will investigate disk evolution and star-formation efficiency in this environment.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
21:53:30.30	+47:16:03.60	IC 5146	ACIS-I	NONE	40

Subject Category: STARS AND WD

Proposal Number: 15200539

Title: Measuring the X-ray Emission Impacting the Planets Orbiting Nearby Low-mass Stars

Type: GO Total Time (ks): 140

PI Name: Alexander Brown

M dwarf planetary systems present a truly exciting opportunity to discover and study the first habitable extrasolar planets in the next 5-10 years. As part of our larger HST MUSCLES project, we propose ACIS-S observations of 4 low-mass exoplanet hosts (3 M dwarfs -- GJ581, GJ1214, GJ849, and 1 K dwarf -- HD97658) that have no existing measurements of their coronal X-ray emission. We will measure their X-ray luminosities and coronal temperatures, and derive the high energy radiation field to facilitate exoplanet atmospheric modeling. These planetary systems allow study of exoplanet atmospheric chemistry and evolution under a wide diversity of physical situations. X-ray heating enhances evaporation and atmospheric escape, which can impact the long-term stability of exoplanetary atmospheres.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
15:19:27.50	-07:43:19.40	GJ581	ACIS-S	NONE	50
17:15:18.90	+04:57:49.70	GJ1214	ACIS-S	NONE	30

Subject Category: STARS AND WD

Proposal Number: 15200550

Title: X-ray Emission from a Radio-Loud Hyperactive L Dwarf

Type: GO Total Time (ks): 25

PI Name: Carl Melis

The origin of radio emission in low-temperature stars and brown dwarfs remains a mystery, given the weak or absent optical and X-ray emission common to these sources. We have now identified the mid-type L dwarf 2MASS1315-2649 as the first low-temperature dwarf that is both a persistent and prodigious H-alpha emitter and a quiescent radio emitter. Given its unique level of magnetic activity, and as one of only four L dwarfs known to exhibit radio emission, we propose 25 ks of Chandra observations to probe the nature of this object's emission mechanisms. The proposed Chandra measurements will enable localization of the source emitting region and the possibility of distinguishing between a variety of competing models for magnetic emission processes in the substellar regime.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
13:15:30.90	-26:49:51.30	2MASS 1315-2649	ACIS-S	NONE	25

Subject Category: STARS AND WD

Proposal Number: 15200565

Title: Accretion-Driven Physics on the Young Star BP Tauri

Type: LP Total Time (ks): 600

PI Name: Nancy Brickhouse

We propose 600 ks with LETG/ACIS-S on the accreting young star BP Tau to study its X-ray emission physics. Our Chandra Large Program on TW Hya has resulted in definitive evidence for accretion, a puzzle over the soft X-ray emission producing O VII emission, and correlations between X-ray and optical signatures related to accretion. Spectral diagnostics from He-like Ne IX constrain all the properties of a simple accretion model, which incorporates the geometrical constraints provided by line-based absorption diagnostics. This deep Chandra spectrum is needed to determine the impact of accretion on a more typical accreting system with different orientation. We will also conduct a campaign to obtain optical photometry, spectroscopy, and spectropolarimetry (for magnetic topology maps).

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
04:19:15.80	+29:06:26.90	BP Tau	ACIS-S	LETG	600

Subject Category: STARS AND WD

Proposal Number: 15200579

Title: A Snapshot Survey of the Most Active Hot Jupiter Systems.

Type: GO Total Time (ks): 30

PI Name: Scott Wolk

X-ray observations of Jupiter mass planets close to their parent stars hold the key to several insights into exoplanets and the star-exoplanet systems. Magnetic and tidal activity are enhanced due to interactions between the star and the planet, there is enhanced high energy deposition into the upper atmosphere of the planet by the star and direct study of the planetary upper atmosphere is possible. Vital experiments have been performed using just two X-ray bright transiting systems. Although the results have been positive and tantalizing, they also stand as singular results. We request a snapshot survey of three transiting hot Jupiter systems which have indications of strong activity and are the best candidates to be bright enough in X-rays for further detailed studies.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
23:18:29.50	+24:53:21.40	WASP 59	ACIS-S	NONE	10
23:13:58.80	+08:45:40.60	WASP 52	ACIS-S	NONE	10
09:53:40.10	-45:39:33.00	WASP 19	ACIS-S	NONE	10

Subject Category: STARS AND WD

Proposal Number: 15200608

Title: Testing the wind-shock paradigm for B-type star X-ray production with theta Carinae (B0.2V)

Type: GO Total Time (ks): 125

PI Name: Veronique Petit

We propose a 125 ks observation of the B0.2V star theta Car, leveraging the unrivaled spectral resolution and sensitivity of the HETG to characterize the kinematics and energetics of the embedded wind shocks. This key star is at the transition between the efficient radiative cooling regime of O supergiants and the low-density, adiabatic regime of the early-B dwarfs. We will use the width the emission lines and the Mg XI f/i ratio to study its shock structure, and test whether an extension of the classical line-driving instabilities operating in O-star to a lower density regime can reproduce the observed X-ray properties of early B-stars. These observations will be essential to improve our classification of the many available broad-band X-ray spectra of B-stars from large cluster studies.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
10:42:57.40	-64:23:40.00	HD 93030	ACIS-S	HETG	125

Subject Category: STARS AND WD

Proposal Number: 15200662

Title: Probing the wind/radiative interactions with the circumstellar material at Periastron Passage of Eta Carinae

Type: GO Total Time (ks): 160

PI Name: Kenji Hamaguchi

The 2009 campaign observations of Eta Carinae revealed multiple plasma components produced by wind-wind collision (WWC) in different stages. X-rays from these plasmas showed emission lines that are not seen in collisionally ionized gas, such as an apparent broadening of the iron K line and unusually strong K-shell emission lines of various ions. These features are important in understanding wind-wind colliding physics, but the snap shot observations in 2009 do not have enough signal-to-noise to investigate them. We therefore propose 3 Chandra observations with deep exposures at critical phases associated with periastron in 2014.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
10:45:03.60	-59:41:04.20	Eta Carinae	ACIS-S	NONE	70
10:45:03.60	-59:41:04.20	Eta Carinae	ACIS-S	NONE	30
10:45:03.60	-59:41:04.20	Eta Carinae	ACIS-S	NONE	60

Subject Category: STARS AND WD

Proposal Number: 15200684

Title: X-Raying the Scorpion's Heart

Type: GO Total Time (ks): 25

PI Name: Vinay Kashyap

We propose to observe the Antares binary system with the HRC-I for 25 ks. This system has an M supergiant primary and a well-separated B2.5V secondary. We will easily detect the shock-front where the winds from the two stars collide. We will also likely detect the shocked wind X-ray emission from the B star. With this observation, we will place unique new constraints on the wind speed and mass loss for both stars. In addition, this will be one of the most sensitive observations of a nearby, resolved, M supergiant system. It is low-risk and low-cost, and has the potential to make a tremendous discovery: the detection of X-ray emission on an M supergiant.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time (ks)
16:29:24.50	-26:25:55.20	Antares	HRC-I	NONE	25

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