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arXiv · 1510.04173

X-rays from Hot Subdwarfs

Sandro Mereghetti·Nicola La Palombara
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Abstract

Thanks to the high sensitivity of the instruments on board the XMM-Newton and Chandra satellites, it has become possible to explore the properties of the X-ray emission from hot subdwarfs. The small but growing sample of hot subdwarfs detected in X-rays includes binary systems, in which the X-rays result from wind accretion onto a compact companion (white dwarf or neutron star), as well as isolated sdO stars in which X-rays are probably due to shock instabilities in the wind. X-ray observations of these low mass stars provide information which can be useful also for our understanding of the winds of more luminous and massive early-type stars and can lead to the discovery of particularly interesting binary systems.

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Sandro Mereghetti, Nicola La Palombara. 2015-10-14. X-rays from Hot Subdwarfs. https://doi.org/10.1016/j.asr.2015.11.022

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