Statistical properties of a sample of periodically variable B-type supergiants. Evidence for opacity

  title={Statistical properties of a sample of periodically variable B-type supergiants. Evidence for opacity},
  author={Karolien Lefever and Joachim Puls and Conny Aerts},
  journal={Astronomy and Astrophysics},
Aims: We have studied a sample of 28 periodically variable B-type supergiants selected from the HIPPARCOS mission and 12 comparison stars covering the whole B-type spectral range. Our goal is to test if their variability is compatible with opacity-driven non-radial oscillations. Methods: We have used the NLTE atmosphere code FASTWIND to derive the atmospheric and wind parameters of the complete sample through line profile fitting. We applied the method to selected H, He, and Si line profiles… 

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