Atmospheric dynamics and the mass loss process in red supergiant stars

  title={Atmospheric dynamics and the mass loss process in red supergiant stars},
  author={Eric Josselin and Bertrand Plez},
  journal={Astronomy and Astrophysics},
Context. Red supergiant stars represent a key phase in the evolution of massive stars. Recent radiative hydrodynamic simulations suggest that their atmospheres may be the location of large-scale convective motions. Aims. As supergiant convection is expected to generate supersonic motions and shocks, we seek constraints on these atmospheric motions and their possible relation with mass-loss rates. Methods. We present high-resolution, visible spectroscopy of a sample of red supergiants (spectral… 

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