Massive stars at low metallicity - Evolution and surface abundances of O dwarfs in the SMC

  title={Massive stars at low metallicity - Evolution and surface abundances of O dwarfs in the SMC},
  author={J-C. Bouret and Thierry M. Lanz and Fabrice Martins and Wagner L. F. Marcolino and D. John Hillier and {\'E}ric Depagne and I. Hubeny},
  journal={Astronomy and Astrophysics},
We study the evolution, rotation, and surface abundances of O-type dwarfs in the Small Magellanic Cloud. We analyzed the UV and optical spectra of twenty-three objects and derived photospheric and wind properties. The observed binary fraction of the sample is ~ 26%, which is compatible with more systematic studies, if one considers that the actual binary fraction is potentially larger owing to low-luminosity companions and that the sample excluded obvious spectroscopic binaries. The location of… Expand
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