Plastic Damping of Alfvén Waves in Magnetar Flares and Delayed Afterglow Emission
Abstract
Magnetar flares generate Alfvén waves bouncing in the closed magnetosphere with energy up to 10^46 erg. We show that on a timescale of 10 ms 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.
Type
Publication
The Astrophysical Journal
Authors
Assistant Professor
Xinyu Li is an assistant professor in the Department of Astronomy, Tsinghua University. He is fond of discovering fundamental physical laws from the vast observation of various astrophysical objects. His research areas are high energy astrophysics, plasma astrophysics and cosmology. His research topics cover a broad range of physical scales: from the smallest fundamental particles like electrons and ultralight axions, to neutron stars, black holes and galaxies, and to the largest scale structure of the universe.