Accepted Cycle 13 Observing Proposals

WD BINARES & CV

Proposal Number	Subject Category	PI Name	Title
13300005	WD BINARIES AND CV	Murray	Chandra Spectroscopy of the Supersoft Binary Candidate XMMU J115113.3-623730
13300077	WD BINARIES AND CV	Predehl	Resolving short supersoft source states of optical novae in the core of M31
13300385	WD BINARIES AND CV	Kong	Close binary populations in metal-rich globular clusters
13300461	WD BINARIES AND CV	Walter	The Galactic Nova KT Eridani in Quiescence
13300810	WD BINARIES AND CV	KAROVSKA	Dynamical Evolution of the Recent Jet in CH Cyg
13300922	WD BINARIES AND CV	Drake	Probing Coronal Supersaturation in Pre-Cataclysmic Binaries with M-type Companions

Subject Category: WD BINARIES AND CV

Proposal Number: 13300005

Title: Chandra Spectroscopy of the Supersoft Binary Candidate XMMU J115113.3-623730

PI Name: Stephen Murray

XMMU J115113.3-623730 is a bright, supersoft X-ray source discovered in outburst phase during an XMM observation. Swift TOO monitoring shows that the source has remained bright, with an overall trend of slightly increasing X-ray flux. Optical records, as well as our follow-up optical photometry and spectroscopy, and radio observations, suggest this is a supersoft binary source that went into outburst in late 2008. Optical monitoring has identified an 8.65 hr orbital period, and Chandra observations with ACIS indicate evidence for orbital variation in the X-ray flux. We propose a 70 ks observation with the HRC/LETG to obtain an uninterrupted light curve over two full orbits of the system, and to search for spectral variations associated with orbital phase.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
11:51:13.30	-62:37:30.00	XMMU J115113.3-623730	HRC-S	LETG	70

Subject Category: WD BINARIES AND CV

Proposal Number: 13300077

Title: Resolving short supersoft source states of optical novae in the core of M31

PI Name: Peter Predehl

We propose to extend the monitoring of the M31 core granted as a XMM-Newton/Chandra proposal in XMM-Newton AO10 by four 19 ks Chandra HRC-I observations equally distributed from mid-February 2012 to mid-March 2012 to determine light curves of the short supersoft source (SSS) states of optical novae. SSS states with <100 d duration indicate accreting massive white dwarfs (WDs). They are proposed as SN-Ia progenitors. Determining their frequency is very important. With a nova rate in the field of ~38/yr and SSS states lasting from weeks to years we will simultaneously follow light curves of many novae. The duration of nova SSS states will allow us to constrain envelope and WD masses. At the same time we will monitor time variability of ~200 M 31 centre X-ray sources, mostly XRBs.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
00:42:44.30	+41:16:09.40	M31	HRC-I	NONE	76

Subject Category: WD BINARIES AND CV

Proposal Number: 13300385

Title: Close binary populations in metal-rich globular clusters

PI Name: Albert Kong

Recent observations of Galactic and extragalactic globular clusters have suggested that bright X-ray sources preferentially reside in metal-rich clusters. The same scenario may also happen for low-luminosity globular cluster X-ray sources. Although Chandra has observed many Galactic globular clusters, majority of them are metal-poor with [Fe/H]<-1 and there is no observational evidence for metal dependence. We propose to use Chandra/HST to study a sample of metal-rich ([Fe/H]>-0.5) globular clusters and to test the prediction that metallicity can affect the population of low-luminosity globular cluster X-ray sources.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
18:09:17.60	-25:54:31.30	NGC6553	ACIS-S	NONE	33
19:11:12.00	+01:01:49.70	NGC6760	ACIS-S	NONE	55
15:28:00.70	-50:40:22.90	NGC5927	ACIS-S	NONE	48
17:25:29.10	-48:25:19.80	NGC6352	ACIS-S	NONE	20

Subject Category: WD BINARIES AND CV

Proposal Number: 13300461

Title: The Galactic Nova KT Eridani in Quiescence

PI Name: Frederick Walter

We request a 75~ksec ACIS-S observation of KT Eridani (Nova Eridani 2009) in order to obtain the spectrum, and look for the orbital period, of this likely-recurrent nova as it enters quiescence. KT Eri is one of the brightest and best studied of this type of novae, and observations of the quiescent system offer opportunities to gain new insights into this class of possible SN Ia progenitors.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
04:47:54.20	-10:10:43.10	KT Eridani	ACIS-S	NONE	75

Subject Category: WD BINARIES AND CV

Proposal Number: 13300810

Title: Dynamical Evolution of the Recent Jet in CH Cyg

PI Name: MARGARITA KAROVSKA

We propose to carry out Chandra ACIS-S observations combined with HST/WFC3 multi-wavelength imaging of the powerful, multi-component jet which was detected in 2008 in the nearby symbiotic CH Cyg. CH Cyg is a fascinating system containing an evolved giant and a wind-accreting white dwarf, and it is one of the few symbiotics showing jet activity, especially in X-rays. Our goal is to measure the physical characteristics of the individual jet components, from the central source to the region of interaction with the circumbinary environment, reaching to within a few AU from the source of the jet. We will determine the characteristics of the central source, and of the inner and the outer jet, and the dynamical evolution, including precession, and kinematics of the ejecta.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
19:24:33.10	+50:14:29.10	CH Cyg	ACIS-S	NONE	90

Subject Category: WD BINARIES AND CV

Proposal Number: 13300922

Title: Probing Coronal Supersaturation in Pre-Cataclysmic Binaries with M-type Companions

PI Name: Jeremy Drake

Evolution of pre-cataclysmic and cataclysmic binaries is thought to be dominated by orbital angular momentum loss through coronally-driven winds of the late-type secondary star. However, coronal activity of stars at the extremes of rotation found in cataclysmic variables (CVs) remains essentially unexplored: existing studies reach to rotation periods of 0.3-0.2 days---significantly longer than the periods of CVs. The aim of this proposal is to explore the X-ray supersaturation regime close to 0.1 day periods using short {\it Chandra} snapshot observations for a small sample of the fastest rotating stars outside of accreting systems. The results will be relevant for understanding the timescales of CV evolution and the possible road to Type~1a supernovae.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
22:37:15.60	+82:10:27.30	HS 2237+8154	ACIS-S	NONE	10
00:59:28.90	-26:31:05.00	LTT560	ACIS-S	NONE	3
00:59:28.90	-26:31:05.00	LTT560	ACIS-S	NONE	3
22:58:48.10	+25:15:43.00	MSPeg	ACIS-S	NONE	8

The Chandra X-Ray Center (CXC) is operated for NASA by the Smithsonian Astrophysical Observatory. 60 Garden Street, Cambridge, MA 02138 USA. Email: cxchelp@head.cfa.harvard.edu Smithsonian Institution, Copyright © 1998-2025. All rights reserved.