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On the X-ray source luminosity distributions in the bulge and disk of M31: First results from XMM-Newton survey

Sergey Trudolyubov·Konstantin Borozdin·William Priedhorsky·Keith Mason·France Cordova
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Abstract

We present luminosity distributions for the X-ray sources detected with XMM-Newton in the bulge and disk of the Andromeda Galaxy (M31). The disk is clearly lacking the brighter sources which dominate X-ray emission from the bulge. This is the first convincing evidence for a difference between bulge and disk X-ray populations in M31. Our results are in good qualitative agreement with the luminosity distributions for low- and high-mass X-ray binaries recently obtained by Grimm et al.(2001) for our Galaxy. This confirms that X-ray population of the disk of M31 is dominated by fainter HMXB sources, while the bulge is populated with brighter LMXBs.

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Sergey Trudolyubov, Konstantin Borozdin, William Priedhorsky, Keith Mason, France Cordova. 2002-03-14. On the X-ray source luminosity distributions in the bulge and disk of M31: First results from XMM-Newton survey. https://doi.org/10.1086/341131

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