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Understanding Pulsations in OB Stars

Published online by Cambridge University Press:  12 April 2016

L. A. Balona*
Affiliation:
South African Astronomical Observatory, P.O. Box 9, Observatory 7935, Cape Town, South Africa

Abstract

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Our understanding of pulsations in β Cep, SPB and ζ Oph stars is discussed. We do not understand why there are no β Cep stars earlier than O9, though the models show that the instability strip extends to hotter stars. The main problem among the SPB stars is why rotation has a strong inhibiting effect on pulsation. The ζ Oph stars are an extension of the β Cep and SPB stars to higher spherical harmonic degrees. The pulsational stability of models of B stars to modes of high degree is discussed. Results are compared with two well observed ζ Oph stars. Although there is good agreement with ζ Oph itself, the periods of the high-degree modes in α Vir are incompatible with model predictions.

Type
Part 6. Variables Close to the Main Sequence
Copyright
Copyright © Astronomical Society of the Pacific 2000

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