Why binary interaction does not necessarily dominate the formation of Wolf-Rayet stars at low metallicity

  title={Why binary interaction does not necessarily dominate the formation of Wolf-Rayet stars at low metallicity},
  author={Tomer Shenar and Avishai Gilkis and Jacco Vink and Hugues Sana and Andreas A. C. Sander},
  journal={arXiv: Solar and Stellar Astrophysics},
Classical Wolf-Rayet (WR) stars are massive, hydrogen depleted, post main-sequence stars that exhibit emission-line dominated spectra. For a given metallicity Z, stars exceeding a certain initial mass M_single(Z) can reach the WR phase through intrinsic mass-loss (single-star channel). Stars of lower masses can reach the WR phase via binary mass transfer (binary channel). It is commonly assumed that the binary channel dominates the formation of WR stars in environments with low Z such as the… 

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