Dissipation of magnetic fields in neutron star crusts due to development of a tearing mode
نویسنده
چکیده
Dissipation of magnetic fields in Hall plasma of neutron star crusts may power persistent high energy emission of a class of strongly magnetized neutrons stars, magnetars. We consider development of a dissipative tearing mode in Hall plasma (electron MHD) and find that its growth rate increases with the wave number of perturbations, reaching a maximum value intermediate between resistive τr and Hall times τH , Γ ∼ 1/ √ τrτH . We argue that the tearing mode may be the principal mechanism by which strong magnetic fields are dissipated in magnetars on times scale of ∼ 10 − 10 yrs powering the persistent X-ray emisison.
منابع مشابه
Magnetic field dissipation in neutron star crusts: from magnetars to isolated neutron stars
Context. We study the non–linear evolution of magnetic fields in neutron star crusts with special attention to the influence of the Hall drift. Aims. Our goal is to understand the conditions for fast dissipation due to the Hall term in the induction equation. We study the interplay of Ohmic dissipation and Hall drift in order to find a timescale for the overall crustal field decay. Methods. We ...
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