A non-axisymmetric magnetorotational instability of a purely toroidal magnetic field

R. Hollerbach; G. Rudiger; M. Schultz; D. Elstner

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A non-axisymmetric magnetorotational instability of a purely toroidal magnetic field

R. Hollerbach·G. Rudiger·M. Schultz·D. Elstner

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Abstract

We consider the flow of an electrically conducting fluid between differentially rotating cylinders, in the presence of an externally imposed toroidal field B_0 (r_i/r) e_phi. It is known that the classical, axisymmetric magnetorotational instability does not exist for such a purely toroidal imposed field. We show here that a non-axisymmetric magnetorotational instability does exist, having properties very similar to the axisymmetric magnetorotational instability in the presence of an axial field.

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R. Hollerbach, G. Rudiger, M. Schultz, D. Elstner. 2006-11-16. A non-axisymmetric magnetorotational instability of a purely toroidal magnetic field. https://arxiv.org/abs/astro-ph/0611534

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