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A new population of X-ray transients in the Galactic Centre

Masaaki Sakano·Robert S. Warwick·Anne Decourchelle·Q. Daniel Wang
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Abstract

A comparison of the XMM-Newton and Chandra Galactic Centre (GC) Surveys has revealed two faint X-ray transients with contrasting properties. The X-ray spectrum of XMM J174544-2913.0 shows a strong iron line with an equivalent width of ~2 keV, whereas that of XMM J174457-2850.3 is characterised by a very hard continuum with photon index ~1.0. The X-ray flux of both sources varied by more than 2 orders of magnitude over a period of months with a peak X-ray luminosity of 5 x 10^34 erg/s. We discuss the nature of these peculiar sources.

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Masaaki Sakano, Robert S. Warwick, Anne Decourchelle, Q. Daniel Wang. 2003-10-06. A new population of X-ray transients in the Galactic Centre. https://arxiv.org/abs/astro-ph/0310140

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