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arXiv · 0710.1804

Observational evidence for the origin of X-ray sources in globular clusters

Frank Verbunt·Dave Pooley·Cees Bassa
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Abstract

Low-mass X-ray binaries, recycled pulsars, cataclysmic variables and magnetically active binaries are observed as X-ray sources in globular clusters. We discuss the classification of these systems, and find that some presumed active binaries are brighter than expected. We discuss a new statistical method to determine from observations how the formation of X-ray sources depends on the number of stellar encounters and/or on the cluster mass. We show that cluster mass is not a proxy for the encounter number, and that optical identifications are essential in proving the presence of primordial binaries among the low-luminosity X-ray sources.

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Frank Verbunt, Dave Pooley, Cees Bassa. 2007-10-09. Observational evidence for the origin of X-ray sources in globular clusters. https://doi.org/10.1017/s1743921308015822

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