Properties of Galactic early-type O-supergiants - A combined FUV-UV and optical analysis

  title={Properties of Galactic early-type O-supergiants - A combined FUV-UV and optical analysis},
  author={J-C. Bouret and D. John Hillier and Thierry M. Lanz and Alex W. Fullerton},
  journal={Astronomy and Astrophysics},
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 conspicuous wind profiles. Using the non-LTE wind code CMFGEN, we simultaneously analyzed the FUV-UV and optical spectral range to determine the photospheric properties and wind parameters. We derived effective temperatures, luminosities, surface gravities, surface abundances, mass-loss rates, wind… 
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