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A Hall--Drift Induced Magnetic Field Instability

M. Rheinhardt·U. Geppert
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Abstract

In the presence of a strong magnetic field and under conditions as realized in the crust and the superfluid core of neutron stars the Hall--drift dominates the field evolution. We show by a linear analysis that for a sufficiently strong large--scale background field depending at least quadratically on position in a plane conducting slab an instability occurs which rapidly generates small--scale fields. Their growth rates depend on the choice of the boundary conditions, increase with the background field strength and may reach $10^3$ times the ohmic decay rate. The effect of that instability on the rotational and thermal evolution of neutron stars is discussed.

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M. Rheinhardt, U. Geppert. 2002-02-12. A Hall--Drift Induced Magnetic Field Instability. https://arxiv.org/abs/astro-ph/0202225

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