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Detection of X-ray bursts in the globular cluster NGC 6652

J. J. M. in 't Zand·F. Verbunt·J. Heise·J. M. Muller·A. Bazzano·M. Cocchi·L. Natalucci·P. Ubertini
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Abstract

Two type I X-ray bursts were detected from a position consistent with the transient X-ray source in NGC 6652 with the Wide Field Camera of the BeppoSAX satellite, strongly suggesting that this transient is a neutron star. Our detection brings to ten the number of X-ray sources in globular clusters in which a type I X-ray burst has been seen, out of twelve known bright sources. The statistical evidence that the fraction of low-mass X-ray binaries which contain a black hole accretor is smaller in globular clusters than in the galactic disk is suggestive, but as yet not compelling.

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J. J. M. in 't Zand, F. Verbunt, J. Heise, J. M. Muller, A. Bazzano, M. Cocchi, L. Natalucci, P. Ubertini. 1997-12-19. Detection of X-ray bursts in the globular cluster NGC 6652. https://arxiv.org/abs/astro-ph/9712272

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