The formation of black-holes in low-mass X-ray binaries

Simon F. Portegies Zwart; Frank Verbunt; Ene Ergma

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The formation of black-holes in low-mass X-ray binaries

Simon F. Portegies Zwart·Frank Verbunt·Ene Ergma

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Abstract

We calculate the formation rates of low-mass X-ray binaries with a black hole. Both a semi-analytic and a more detailed model predict formation rates two orders of magnitude lower than derived from the observations. Solution of this conundrum requires either that stars with masses less than 20M$_\odot$ can evolve into a black hole, or that stellar wind from a member of a binary is accompanied by a much larger loss of angular momentum than hitherto assumed.

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Simon F. Portegies Zwart, Frank Verbunt, Ene Ergma. 1997-01-08. The formation of black-holes in low-mass X-ray binaries. https://arxiv.org/abs/astro-ph/9701037

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