Bright X-ray Transients in M31: 2004 July XMM-Newton Observations

Abstract

We present the results of X-ray observations of four bright transients sources detected in the July 2004 XMM-Newton observations of the central bulge of M31. Two X-ray sources, XMMU J004315.5+412440 and XMMU J004144.7+411110, were discovered for the first time. Two other sources, CXOM31 J004309.9+412332 and CXOM31 J004241.8+411635, were previously detected by Chandra. The properties of the sources suggest their identification with accreting binary systems in M31. The X-ray spectra and variability of two sources, XMMU J004144.7+411110 and CXOM31 J004241.8+411635, are similar to that of the Galactic black hole transients, making them a good black hole candidates. The X-ray source XMMU J004315.5+412440 demonstrates a dramatic decline of the X-ray flux on a time scale of three days, and a remarkable flaring behavior on a short time scales. The X-ray data on XMMU J004315.5+412440 and CXOM31 J004309.9+412332 suggest that they can be either black hole or neutron star systems. Combining the results of 2000-2004 XMM observations of M31, we estimate a total rate of the bright transient outbursts in the central region of M31 to be 6-12 per year, in agreement with previous studies.

8 pages, 3 figures, uses emulateapj style. Submitted to ApJ

References in corpus (8)

• XMM-Newton survey of M 31
• A Synoptic X-ray Study of M31 with the Chandra-HRC
• M31 Globular Cluster X-ray Sources: XMM-Newton and Chandra results
• A Catalog of Transient X-ray Sources in M31
• Discovery of disc precession in the M31 dipping X-ray binary Bo 158
• Chandra and Hubble Study of a New Transient X-ray Source in M31
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• A Soft X-ray Transient in the M31 Bulge

Cited by in corpus (10)

• The deep XMM-Newton Survey of M 31
• A study of the population of LMXBs in the bulge of M31
• Wide-Field Survey of Globular Clusters in M31. II. Kinematics of the Globular Cluster System
• Mass transfer during low mass X-ray transient decays
• Time variability of X-ray sources in the M 31 centre field
• X-ray source variability study of the M 31 central field using Chandra HRC-I
• A Transient Black-Hole Low-Mass X-Ray Binary Candidate in Centaurus A
• Three X-ray transients in M31 observed with Swift
• A Transient Sub-Eddington Black Hole X-ray Binary Candidate in the Dust Lanes of Centaurus A
• NuSTAR view of the central region of M 31