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

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.

5 pages, 4 figures, Astronomical Notes, submitted The proceedings of the HELAS IV conference, Lanzarote 1-5 February, 2010, Eds. T. Roca Cortes, P. Palle and S. Jimenez Reyes

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Cited by in corpus (4)

• Multisite spectroscopic seismic study of the beta Cep star V2052 Oph: inhibition of mixing by its magnetic field
• The $\beta$ Cep/SPB star 12 Lacertae: extended mode identification and complex seismic modelling
• gamma Peg: testing Vega-like magnetic fields in B stars
• Computation of atomic astrophysical opacities