New Results on Pulsating OB Stars

Pawel Moskalik

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arXiv · astro-ph/9505057

New Results on Pulsating OB Stars

Pawel Moskalik

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Abstract

Until very recently the physical mechanism driving oscillations in $β$~Cep and other early type stars has been a mystery. The breakthrough came with the publication of new OPAL and OP opacity data. Model calculations with the new opacities have demonstrated that the pulsations are driven by the familiar $κ$-mechanism, acting in the metal opacity bump at $T \approx 2 \times 10^5$K. The mechanism excites the low order $p$- and $g$-modes in the upper part of the instability strip and the high order $g$-modes in the lower part of the strip. The theoretical instability domains agree well with the observed domains of the $β$~Cep and the SPB stars. In this review I present these recent theoretical results and discuss their consequences for our understanding of B stars pulsations.

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Pawel Moskalik. 1995-05-12. New Results on Pulsating OB Stars. https://arxiv.org/abs/astro-ph/9505057

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