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arXiv · 1004.2366

Complex asteroseismology of the hybrid B-type pulsator $\gamma$ Pegasi: a test of stellar opacities

Przemysław Walczak·Jadwiga Daszyńska-Daszkiewicz
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Abstract

Using the updated oscillation spectrum of $\gamma$ Pegasi, we construct a set of seismic models which reproduce two pulsational frequencies corresponding to the $\ell=0$, p$_1$ and $\ell=1$, g$_1$ modes. Then, we single out models which reproduce other well identified modes. Finally, we extend our seismic modelling by a requirement of fitting also values of the complex, nonadiabatic parameter $f$ associated to each mode frequency. Such complex asteroseismology of the B-type pulsators provides a unique test of stellar metallicity and opacities. In contrast to our previous studies, results for $\gamma$ Peg indicate that both opacity tables, OPAL and OP, are equally preferred.

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Przemysław Walczak, Jadwiga Daszyńska-Daszkiewicz. 2010-04-14. Complex asteroseismology of the hybrid B-type pulsator $\gamma$ Pegasi: a test of stellar opacities. https://doi.org/10.1002/asna.201011456

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