Fast radio bursts and their high-energy counterpart from magnetar magnetospheres

Understand

The recent discovery of a Galactic fast radio burst (FRB) occurring simultaneously with an X-ray burst (XRB) from the Galactic magnetar SGR J1935+2154 implies that at least some FRBs arise from magnetar activities.

• We propose that FRBs are triggered by crust fracturing of magnetars, with the burst event rate depending on the magnetic field strength in the crust.
• Since the crust fracturing rate is relatively higher in polar regions, FRBs are preferred to be triggered near the directions of multipolar magnetic poles.
• Crust fracturing produces Alfv\'en waves, forming a charge starved region in the magnetosphere and leading to non-stationary pair plasma discharges.