Dipole low-order g-mode instability of metal-poor low-mass main-sequence stars due to the inline image mechanism

Authors

  • Takafumi Sonoi,

    Corresponding author
    1. Department of Astronomy, Graduate School of Science, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan
    Search for more papers by this author
  • Hiromoto Shibahashi

    Corresponding author
    1. Department of Astronomy, Graduate School of Science, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan
    Search for more papers by this author

E-mail: sonoi@astron.s.u-tokyo.ac.jp; shibahashi@astron.s.u-tokyo.ac.jp

ABSTRACT

We analysed the vibrational stability of metal-poor low-mass main-sequence stars due to the ɛ mechanism. Since outer convection zones of metal-poor stars are limited only to the very outer layers, uncertainty in the treatment of convection does not affect the result significantly. We found that the dipole g1 and g2 modes definitely become unstable due to the ɛ mechanism for inline image. Besides that, we found that as the metallicity decreases the mass range of ɛ-mechanism instability extends toward higher mass.

Ancillary