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

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.

arXiv comment10 pages, 7 figures, to appear in IAUS 246, Dynamical evolution of dense stellar systems, ed. E. Vesperini

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Cited by in corpus (11)

• An Analytic Model for Blue Straggler Formation in Globular Clusters
• Low-Mass X-ray Binaries and Globular Clusters in Centaurus A
• X-ray and optical observations of M55 and NGC 6366: evidence for primordial binaries
• The Swift Bulge Survey: Motivation, Strategy, and First X-ray Results
• Study of HST counterparts to Chandra X-ray sources in the Globular Cluster M71
• The X-ray Emissivity of Low-Density Stellar Populations
• A deep Chandra survey for faint X-ray sources in the Galactic globular cluster M30, and searches for optical and radio counterparts
• Identifications of Faint Chandra Sources in the Globular Cluster M3
• Exotica in the Globular Cluster M4, Studied with Chandra, HST, and the VLA
• X-rays from the Eclipsing Millisecond Pulsar PSR J1740-5340 in the Globular Cluster NGC 6397
• Exploration of faint X-ray and radio sources in the massive globular cluster M14: A UV-bright counterpart to Nova Ophiuchus 1938