Are there any stable magnetic fields in barotropic stars?

Understand

We construct barotropic stellar equilibria, containing magnetic fields with both poloidal and toroidal field components.

• We extend earlier results by exploring the effect of different magnetic field and current distributions.
• Our results suggest that the boundary treatment plays a major role in whether the poloidal or toroidal field component is globally dominant.
• Using time evolutions we provide the first stability test for mixed poloidal-toroidal fields in barotropic stars, finding that all these fields suffer instabilities due to one of the field components: these are localised around the pole for toroidal-dominated equilibria and in the closed-field line region for poloidal-dominated equilibria.