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arXiv · 1109.5148

The Magnetised Bellows of Betelgeuse

Anand Thirumalai·Jeremy S. Heyl
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Abstract

We present calculations for a magnetised hybrid wind model for Betelegeuse ($α- $Orionis). The model is a direct application of our previously derived theory, combining a canonical Weber-Davis (WD) stellar wind with dust grains in the envelope of an AGB star \citep[see][]{Thirumalai2010}. The resulting hybrid picture provides a mechanism for solving the problem of lifting stellar material up from the photosphere \citep[e.g.][] {Harper2009,Guandalini2006,Jura1984} and into the circumstellar envelope. It also predicts wind velocities in agreement with current estimates. Our approach reveals that magnetic fields in supergiant stars like Betelgeuse \citep[see][]{Auriere2010}, may play a vital role in determining the nature of the stellar outflow and consequently, opens a new avenue of investigation in the field of hybrid stellar winds.

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Anand Thirumalai, Jeremy S. Heyl. 2012-02-06. The Magnetised Bellows of Betelgeuse. https://doi.org/10.1111/j.1365-2966.2012.20703.x

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