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Dynamo action in late-type giants

S. B. F. Dorch
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Abstract

Recent numerical MHD simulations suggest that magnetic activity may occur in late-type giants. A entire red supergiant with stellar parameters equal to Betelgeuse was modelled in 3d with the high-order "Pencil Code". Linear kinematic and non-linear saturated dynamo action are found and the non-linear magnetic field saturates at a super-equipartition value, while in the linear regime two different modes of dynamo action are found. Magnetic activity of late-type giants, if it exists, may influence dust and wind formation and possibly lead to the heating of the outer atmospheres of these stars.

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S. B. F. Dorch. 2004-09-08. Dynamo action in late-type giants. https://arxiv.org/abs/astro-ph/0409192

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