English

On the Stability of Non Force-Free Magnetic Equilibria in Stars

Solar and Stellar Astrophysics 2015-05-20 v1

Abstract

The existence of stable magnetic configurations in white dwarfs, neutron stars and various non-convective stellar {regions} is now well recognized. It has recently been shown numerically that various families of equilibria, including axisymmetric mixed poloidal-toroidal configurations, are stable. Here we test the stability of an analytically-derived non force-free magnetic equilibrium, using three-dimensional magnetohydrodynamic simulations: the mixed configuration is compared with the dynamical evolution of its purely poloidal and purely toroidal components, both known to be unstable. The mixed equilibrium shows no sign of instability under white noise perturbations. {This configuration therefore provides a good description of magnetic equilibrium topology inside non-convective stellar objects and will be useful to initialize magneto-rotational transport in stellar evolution codes.

Keywords

Cite

@article{arxiv.1009.5384,
  title  = {On the Stability of Non Force-Free Magnetic Equilibria in Stars},
  author = {V. Duez and J. Braithwaite and S. Mathis},
  journal= {arXiv preprint arXiv:1009.5384},
  year   = {2015}
}

Comments

Accepted for publication in ApJL