The origin of subdwarf B stars – I. The formation channels

@article{Han2002TheOO,
  title={The origin of subdwarf B stars – I. The formation channels},
  author={Zhan-wen Han and Philipp Podsiadlowski and Pierre F. L. Maxted and Thomas R. Marsh and Natasha Ivanova},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={2002},
  volume={336},
  pages={449-466}
}
Subdwarf B (sdB) stars (and related sdO/sdOB stars) are believed to be helium-core-burning objects with very thin hydrogen-rich envelopes. In recent years it has become increasingly clear from observational surveys that a large fraction of these objects are members of binary systems. To understand their formation better, we present the results of a detailed investigation of the three main binary evolution channels that can lead to the formation of sdB stars: the common-envelope (CE) ejection… 
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