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Magnetic Oscillations in Radiative Stars

Published online by Cambridge University Press:  12 April 2016

E. J. Zita
E. J. Zita*
Affiliation:
The Evergreen State College, Olympia, WA, 98505, USA

Abstract

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What drives acoustic modes in magnetic, radiative stars, such as the rapidly oscillating Ap (roAp) stars? We propose that oscillations in the shape of the magnetic field can drive magnetosonic waves, which are observed as p modes. The force-free atmosphere minimizes magnetic energy. If the field is strong enough, the magnetic configuration can oscillate about its equilibrium state. Initial calculations showed that the wavenumbers, frequencies, and available energy are consistent with observations of roAp stars (Zita 1997). We present the results of new calculations and proposed tests of our model. We also discuss the resultant < υ × b > dynamo, which may shed light on observations in B stars.

Type
Part 5. Theoretical Models of Classical Pulsating Stars
Information
International Astronomical Union Colloquium , Volume 176: The Impact of Large-Scale Surveys on Pulsating Star Research , 2000 , pp. 386 - 387
Copyright
Copyright © Astronomical Society of the Pacific 2000

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