Pulsational instability of yellow hypergiants

  title={Pulsational instability of yellow hypergiants},
  author={Yu. A. Fadeyev},
  journal={Astronomy Letters},
Instability of population I (X = 0.7, Z = 0.02) massive stars against radial oscillations during the post-main-sequence gravitational contraction of the helium core is investigated. Initial stellar masses are in the range 65M⊙ ≤ MZAMS ≤ 90M⊙. In hydrodynamic computations of self-exciting stellar oscillations we assumed that energy transfer in the envelope of the pulsating star is due to radiative heat conduction and convection. The convective heat transfer was treated in the framework of the… Expand

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