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… 
The MiMeS Survey of Magnetism in Massive Stars: CNO surface abundances of Galactic O stars
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We aim to constrain the properties and evolutionary status of early and mid-spectral type supergiants (from O4 to O7.5). These posses the highest mass-loss rates among the O stars, and exhibit
We present projected rotational velocity values for 97 Galactic, 55 SMC, and 106 LMC O-B type stars from archival FUSE observations. The evolved and unevolved samples from each environment are
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The Effective Temperatures of Hot Stars. II. The Early-O Types*
We derived the stellar parameters of a sample of Galactic early-O type stars by analyzing their UV and far-UV spectra from the Far Ultraviolet Spectroscopic Explorer (905-1187 A), the International
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New radial-velocity observations of 37 O- and B stars in the very young open cluster NGC 6231 confirm the high frequency of short-period spectroscopic binaries on the upper main sequence. Among the
Lower mass loss rates in O-type stars: Spectral signatures of dense clumps in the wind of two Galactic O4 stars
We have analyzed the far-ultraviolet spectrum of two Galactic O4 stars, the O4If+ supergiant HD 190429A and the O4V((f)) dwarf HD 96715, using archival FUSE and IUE data. We have conducted a
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We study the stellar and wind properties of a sample of Galactic O dwarfs to track the conditions under which weak winds (i.e mass loss rates lower than � 10 −8 M⊙ yr −1 ) appear. The sample is
Quantitative Spectroscopy of O Stars at Low Metallicity: O Dwarfs in NGC 346*
We present the results of a detailed analysis of the properties of dwarf O-type stars in a metal-poor environment. High-resolution, high-quality ultraviolet and optical spectra of six O-type stars in