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Rotational Modulation in Be Stars

  • L. A. Balona
Chapter
Part of the Astrophysics and Space Science Proceedings book series (ASSSP, volume 31)

Abstract

The broad peaks in the periodograms of the light variations of Be stars do not resolve into individual frequencies even in a long time series. Recent CoRoT observations, in particular, clearly demonstrate their stochastic nature. These peaks, which have frequencies indistinguishable from the rotational frequency and its first harmonic, have generally been attributed to l = 2 nonradial pulsation (NRP). Stochastic variation with the rotational period is an inevitable consequence of localized mass loss for any mass-loss mechanism, including NRP. It is evident that the broad peaks are just a result of co-rotating circumstellar gas clouds. A simple model in which the mass loss is a result of magnetic flaring explains all major characteristics of Be stars.

Keywords

Rotational Velocity Spectral Type Light Variation Circumstellar Disk Rapid Rotation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  1. 1.South African Astronomical ObservatoryCape TownSouth Africa

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