X-ray emission from magnetic dissipation in the magnetar magnetosphere

Abstract

Magnetic dissipation through decay of Alfven waves in the magnetar magnetosphere is discussed. Transport of magnetic fields in the star leads to dissipation of the magnetic energy through either direct internal heating or transferring of the energy in waves that decay in the magnetar magnetosphere. In the latter case, the Alfven waves are excited by crust dislocations or elastic waves underneath the star's surface. It is suggested that these Alfven waves can decay into ion sound waves which can be effectively damped leading to strong plasma heating. Hot plasmas expand producing transient X-rays.