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arXiv · 1405.4568

Pulsations of Pre-White Dwarfs with Hydrogen-dominated Atmospheres

Kazuhiro Maeda·Hiromoto Shibahashi
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Abstract

We carried out a fully non-adiabatic analysis for nonradial oscillations of pre-white dwarfs evolved from the post-Asymptotic Giant Branch (AGB) with hydrogen-dominated envelopes. It is shown that nuclear reactions in the hydrogen burning-shell excite low-degree g-modes in the period range of about 40-200 s for the pre-white dwarf models with Teff=40,000 K - 300,000 K. It is also shown that the amount of hydrogen {has} a significant influence on the instability domain of such pre-white dwarfs in the Hertzsprung-Russel (H-R) diagram. Thus, the thickness of hydrogen-dominated envelopes may be well constrained by observing the presence of the g-mode oscillations.

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Kazuhiro Maeda, Hiromoto Shibahashi. 2014-05-19. Pulsations of Pre-White Dwarfs with Hydrogen-dominated Atmospheres. https://doi.org/10.1093/pasj%2Fpsu051

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