Mixing zones in magnetized differentially rotating stars

¹ Departament de Fisica Aplicada, Universitat d'Alacant, Ap. Correus 99, 03080 Alacant, Spain e-mail: vadim.urpin@uv.es
² A. F. Ioffe Institute of Physics and Technology and the Isaac Newton Institute of Chili, Branch in St. Petersburg, 194021 St. Petersburg, Russia

Received: 5 April 2005
Accepted: 28 September 2005

Abstract

We study the secular instability of magnetized differentially rotating radiative zones taking account of viscosity and magnetic and thermal diffusivities. This considered instability generalizes the well-known Goldreich-Schubert-Fricke instability for the case of a sufficiently strong magnetic field. In magnetized stars, instability can lead to formation of non-spherical, unstable zones where weak turbulence mixes the material between the surface and interiors. Such unstable zones can manifest themselves by a non-spherical distribution of elements on the stellar surface.