The rate of period change in pulsating DB white dwarf stars

  title={The rate of period change in pulsating DB white dwarf stars},
  author={Alejandro H. C{\'o}rsico and Leandro G. Althaus},
  journal={Astronomy and Astrophysics},
In this work, we present the theoretically expected rates of pulsation period change for V777 Her (DBV) vari- able stars. To this end we employ new evolutionary models representative of pulsating DB white dwarf stars computed in a self-consistent way with the predictions of time-dependent element diffusion. At the hot edge of the DB instability strip, the envelopes of the models are characterized by a diffusion-induced double-layered chemical structure. We compute the numerical values of rates… 
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