Revised instability domains of SPB and β Cephei stars

Abstract

The excitation of pulsation modes in β Cephei and Slowly Pulsating B stars is known to be very sensitive to opacity changes in the stellar interior where T ˜ 2 × 105 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 {&} 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.