Mapping the Instability Domains of GW Vir Stars in the Effective Temperature-Surface Gravity Diagram

  title={Mapping the Instability Domains of GW Vir Stars in the Effective Temperature-Surface Gravity Diagram},
  author={Pierre-Olivier Quirion and Gilles Fontaine and Pierre Brassard},
  journal={The Astrophysical Journal Supplement Series},
  pages={219 - 248}
We present the results of a detailed stability study of models of GW Vir pulsators. These are extremely hot, evolved, and compact stars that are on their way to the white dwarf cooling phase and that show multiperiodic luminosity variations due to gravity-mode pulsational instabilities. Our nonadiabatic survey confirms that cyclic ionization of carbon and oxygen is at the origin of the GW Vir phenomenon. We find that the extent of the instability domain in the log g-Teff plane is a strong… 

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