Chandra Observations of the Faintest Low-Mass X-ray Binaries

Abstract

There exists a group of persistently faint galactic X-ray sources that, based on their location in the galaxy, high L_x/L_opt, association with X-ray bursts, and absence of low frequency X-ray pulsations, are thought to be low-mass X-ray binaries (LMXBs). We present results from Chandra observations for eight of these systems: 4U 1708-408, 2S 1711-339, KS 1739-304, SLX 1735-269, GRS 1736-297, SLX 1746-331, 1E 1746.7-3224, and 4U 1812-12. Locations for all sources, excluding GRS 1736-297, SLX 1746-331, and KS 1739-304 (which were not detected) were improved to 0.6" error circles (90% confidence). Our observations support earlier findings of transient behavior of GRS 1736-297, KS 1739-304, SLX 1746-331, and 2S 1711-339 (which we detect in one of two observations). Energy spectra for 4U 1708-408, 2S 1711-339, SLX 1735-269, 1E 1746.7-3224, and 4U 1812-12 are hard, with power law indices typically 1.4-2.1, which are consistent with typical faint LMXB spectra.

arXiv comment15 pages, 3 figures. Accepted by ApJ

References in corpus (11)

• Millisecond Oscillations in X-Ray Binaries
• A Unified Description of the Timing Features of Accreting X-ray Binaries
• The broad-band power spectra of X-ray binaries
• Hard X-ray Emission From Low Mass X-ray Binaries
• Modeling the Low State Spectrum of the X-Ray Nova XTE J1118+480
• Discovery of 424 ms pulsations from the radio-quiet neutron star in the PKS 1209-52 supernova remnant
• BeppoSAX Wide Field Cameras observations of six type I X-ray bursters
• Identification of selected sources from the ROSAT Galactic Plane Survey - I
• A possible faint near-infrared counterpart to the AXP 1E~2259+58.6
• Simultaneous BeppoSAX and Rossi X-ray Timing Explorer observations of 4U1812-12
• Discovery of type-I X-ray bursts from the low-mass X-ray binary 4U 1708-40

Cited by in corpus (26)

• Thermonuclear (type-I) X-ray bursts observed by the Rossi X-ray Timing Explorer
• The 70 Month Swift-BAT All-Sky Hard X-Ray Survey
• A Global Spectral Study of Black Hole X-ray Binaries
• The 22-Month Swift-BAT All-Sky Hard X-ray Survey
• Six new candidate ultracompact X-ray binaries
• The Multi-INstrument Burst ARchive (MINBAR)
• The Hot Gas Content of Low-Luminosity Early-Type Galaxies and the Implications Regarding Supernova Heating and AGN Feedback
• Analysing the atolls: X-ray spectral transitions of accreting neutron stars
• A Global Study of the Behaviour of Black Hole X-ray Binary Discs
• The Low Quiescent X-Ray Luminosity of the Neutron Star Transient XTE J2123-058
• On the nature of two low M-dot X-ray bursters: 1RXS J170854.4-321857 and 1RXS J171824.2-402934
• Restless quiescence: thermonuclear flashes between transient X-ray outbursts
• Two new candidate ultra-compact X-ray binaries
• UltraCompCAT: a comprehensive Catalogue of Ultra-Compact and Short Orbital Period X-ray Binaries
• Where Are Be/black-hole Binaries?
• WISE Detection of the Galactic Low-Mass X-Ray Binaries
• A catalogue of unusually long thermonuclear bursts on neutron stars
• The quasi-persistent neutron star soft X-ray transient 1M 1716-315 in quiescence
• INTEGRAL high energy behaviour of 4U 1812-12
• A Lack of Radio Emission from Neutron Star Low Mass X-ray Binaries
• Sample of LMXBs in the Galactic bulge. I. Optical and near-infrared constraints from the Virtual Observatory
• A Limit on the Number of Isolated Neutron Stars Detected in the ROSAT All-Sky Survey Bright Source Catalog
• Identifying a black hole X-ray transient in M31 with XMM-Newton and Chandra
• Back to business: SLX 1746--331 after 13 years of silence
• Optical spectroscopy of 4U 1812-12: an ultra-compact X-ray binary seen through an H II region
• A tentative 114-minute orbital period challenges the ultra-compact nature of the X-ray binary 4U 1812-12