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X-rays from old star clusters

Frank Verbunt
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Abstract

A brief overview is given of X-ray observations of old clusters. Most X-ray sources in old open clusters are interacting binaries, formed via evolution of a primordial binary, and emitting X-rays because of magnetic activity; however, a sizable fraction of the cluster sources is not well understood, including some of the most luminous ones. Globular clusters appear to contain fewer magnetically active X-ray sources than expected if one scales from old open clusters by mass.

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Frank Verbunt. 1999-07-15. X-rays from old star clusters. https://arxiv.org/abs/astro-ph/9907202

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