Magnetic Flares of Merging Neutron stars and Magnetars
Magnetars are the most magnetized neutron stars in the Universe. Their magnetic field even exceeds the critical quantum, Schwinger, field. Phenomena happening in magnetospheres of these extreme objects are produced by the dramatic interplay of quantum electrodynamics and relativistic plasma physics. Of particular interest are flares and bursts powered by the release of the enormous magnetic energy inside magnetars. Recently, magnetars were associated with (at least some) Fast Radio Bursts — enigmatic millisecond-long bursts of extremely bright radio emission.
My group uses powerful numerical simulations to understand the dynamics of magnetic flares and their observed emission. Recent work has focused on revealing the three-dimensional dynamics of twisted magnetic flux tubes in magnetar magnetospheres (paper 1), potential mechanism of producing Fast Radio Bursts through magnetic reconnection (paper 2), and modeling of similar flares expected in magnetospheres of neutron stars just before they merge (paper 3, paper 4).
Emission of low-frequency radiation during the collision of the fast magnetosonic pulse produced by the magnetar flare with the magnetospheric current sheet (Mahlmann et. al., 2022). Magnetic reconnection forced by the collision produces small-scale magnetic islands (``plasmoids’’) which collide with each other and emit electromagnetic waves. This mechanism may be the source of bright extragalactic Fast Radio Bursts.
