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arXiv · 1210.5162

Ultra-compact X-ray binaries with high luminosity: a key for a new scenario

Konstantin Pavlovskii·Natalia Ivanova
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Abstract

Ultra-compact X-ray binaries (UCXBs) are accreting systems with periods less than 1 hour, which qualifies them to contain a degenerate donor-companion. One would expect such systems to have the easiest theoretical explanation, compared to other kinds of X-ray binaries. Nonetheless, current theory fails to explain high mass transfer (MT) rates in three recently well observed long-period UCXBs. We find that this range of MT rates can be maintained if the donor is a remnant of an out-of-thermal-equilibrium naked core of a giant which was revealed in a very recent episode of a common envelope (CE) event.

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Konstantin Pavlovskii, Natalia Ivanova. 2012-10-18. Ultra-compact X-ray binaries with high luminosity: a key for a new scenario. https://doi.org/10.1017/s1743921312024544

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