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arXiv · 1505.03465

Plastic damping of Alfv\'en waves in magnetar flares and delayed afterglow emission

Xinyu Li·Andrei M. Beloborodov
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Abstract

Magnetar flares generate Alfv\'en waves bouncing in the closed magnetosphere with energy up to $\sim 10^{46}$ erg. We show that on a 10-ms timescale the waves are transmitted into the star and form a compressed packet of high energy density. This packet strongly shears the stellar crust and initiates a plastic flow, heating the crust and melting it hundreds of meters below the surface. A fraction of the deposited plastic heat is eventually conducted to the stellar surface, contributing to the surface afterglow months to years after the flare. A large fraction of heat is lost to neutrino emission or conducted into the core of the neutron star.

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Xinyu Li, Andrei M. Beloborodov. 2015-05-13. Plastic damping of Alfv\'en waves in magnetar flares and delayed afterglow emission. https://doi.org/10.1088/0004-637x/815/1/25

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