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arXiv · 1011.0398

A Large Catalogue of Ultraluminous X-ray Source Candidates in Nearby Galaxies

D. J. Walton·J. C. Gladstone·T. P. Roberts·A. C. Fabian
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Abstract

Since their discovery, Ultraluminous X-ray sources (ULXs) have attracted attention due to their combination of extreme luminosities and extra-nuclear locations. However, they are a fairly rare phenomenon, and attempts to investigate the general properties of the population have been hindered by a relative lack of known sources. Here, we present a large catalogue of ULX candidates including 655 detections of 475 discrete sources, based on the 2XMM Serendipitous Survey. To demonstrate the potential of such a resource, we present some scientific analysis of this population, focusing on the spectral turnover seen, often at ~6 keV, in the highest quality ULX data. We also demonstrate how the recent reflection and Comptonisation interpretations of this feature may be distinguished observationally in the future, specifically using NGC 4517 ULX1, a previously unanalysed source with high quality data, as an example case.

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D. J. Walton, J. C. Gladstone, T. P. Roberts, A. C. Fabian. 2010-11-01. A Large Catalogue of Ultraluminous X-ray Source Candidates in Nearby Galaxies. https://doi.org/10.1002/asna.201011498

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