Hydromagnetic Instabilities in Neutron Stars

Understand

We model the non-linear ideal magnetohydrodynamics of poloidal magnetic fields in neutron stars in general relativity assuming a polytropic equation of state.

• We identify familiar hydromagnetic modes, in particular the 'sausage/varicose' mode and 'kink' instability inherent to poloidal magnetic fields.
• The evolution is dominated by the kink instability, which causes a cataclysmic reconfiguration of the magnetic field.
• The system subsequently evolves to new, non-axisymmetric, quasi-equilibrium end-states.