Probing the weak wind phenomenon in Galactic O-type giants

  title={Probing the weak wind phenomenon in Galactic O-type giants},
  author={E. S. G. de Almeida and Wagner L. F. Marcolino and J-C. Bouret and Claudio Bastos Pereira},
  journal={Astronomy \& Astrophysics},
Aims. Analyses of Galactic late O dwarfs (O8-O9.5V stars) raised the “weak wind problem”: spectroscopic mass-loss rates (Ṁ) are up to two orders of magnitude lower than the theoretical values. We investigated the stellar and wind properties of Galactic late O giants (O8-O9.5III stars). These stars have luminosities log (L⋆ ∕ L⊙) ~ 5.2, which is the critical value (onset of weak winds) proposed in the literature. Methods. We performed a spectroscopic analysis of nine O8-O9.5III stars in the… 
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