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arXiv · 1105.1895

Hydromagnetic Instabilities in Neutron Stars

Paul D. Lasky·Burkhard Zink·Kostas D. Kokkotas·Kostas Glampedakis
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Abstract

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. The existence of this branch of stable quasi-equilibria may have consequences for magnetar physics, including flare generation mechanisms and interpretations of quasi-periodic oscillations.

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Paul D. Lasky, Burkhard Zink, Kostas D. Kokkotas, Kostas Glampedakis. 2011-05-24. Hydromagnetic Instabilities in Neutron Stars. https://doi.org/10.1088/2041-8205%2F735%2F1%2Fl20

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