On the excitation of PG1159-type pulsations
نویسندگان
چکیده
Stability properties are presented of dipole and quadrupole nonradial oscillation modes of model stars that experienced a late helium shell flash on their way to the white-dwarf cooling domain. The computed instability domains are compared with the observed hot variable central stars of planetary nebulae and the GW Vir pulsators.
منابع مشابه
Low-mass, helium-enriched PG1159 stars: a possible evolutionary origin and the implications for their pulsational stability properties
Aims. We examine a recently–proposed evolutionary scenario that could explain the existence of the low–mass, helium– enriched PG1159 stars. We focus in particular on the study of the pulsational stability properties of the evolutionary models predicted by such scenario. Methods. We assess the overstability of pulsation g−modes of stellar models as evolution proceeds along the PG1159 domain. Ste...
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