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arXiv · 1309.6180

What controls the large-scale magnetic fields of M dwarfs?

T. Gastine·J. Morin·L. Duarte·A. Reiners·U. Christensen·J. Wicht
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Abstract

Observations of active M dwarfs show a broad variety of large-scale magnetic fields encompassing dipole-dominated and multipolar geometries. We detail the analogy between some anelastic dynamo simulations and spectropolarimetric observations of 23 M stars. In numerical models, the relative contribution of inertia and Coriolis force in the global force balance -estimated by the so-called local Rossby number- is known to have a strong impact on the magnetic field geometry. We discuss the relevance of this parameter in setting the large-scale magnetic field of M dwarfs.

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T. Gastine, J. Morin, L. Duarte, A. Reiners, U. Christensen, J. Wicht. 2013-09-24. What controls the large-scale magnetic fields of M dwarfs?. https://doi.org/10.1017/s1743921314001987

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