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arXiv · 0706.3632

Revised instability domains of SPB and beta Cephei stars

Andrea Miglio·Josefina Montalban·Marc-Antoine Dupret
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Abstract

The excitation of pulsation modes in beta Cephei and Slowly Pulsating B stars is known to be very sensitive to opacity changes in the stellar interior where T~2 10^5 K. In this region differences in opacity up to ~50% can be induced by the choice between OPAL and OP opacity tables, and between two different metal mixtures (Grevesse and Noels 1993 and Asplund et al. 2005). We have extended the non-adiabatic computations presented in Miglio et al. (2007) towards models of higher mass and pulsation modes of degree l=3, and we present here the instability domains in the HR- and log(P)-log(Teff) diagrams resulting from different choices of opacity tables, and for three different metallicities.

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Andrea Miglio, Josefina Montalban, Marc-Antoine Dupret. 2007-06-25. Revised instability domains of SPB and beta Cephei stars. https://doi.org/10.1553/cia151s48

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