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arXiv · astro-ph/0509693

A differential rotation driven dynamo in a stably stratified star

J. Braithwaite·H. C. Spruit
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Abstract

We present numerical simulations of a self-sustaining magnetic field in a differentially rotating non-convective stellar interior. A weak initial field is wound up by the differential rotation; the resulting azimuthal field becomes unstable and produces a new meridional field component, which is then wound up anew, thus completing the `dynamo loop'. This effect is observed both with and without a stable stratification. A self-sustained field is actually obtained more easily in the presence of a stable stratification. The results confirm the analytical expectations of the role of Tayler instability.

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J. Braithwaite, H. C. Spruit. 2005-09-22. A differential rotation driven dynamo in a stably stratified star. https://doi.org/10.1051/0004-6361%3A20054241

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