Magnetars with Low Magnetospheric Twist
|Category||Progenitor||Type||Energy Mechanism||Emission Mechanism||Counterparts||References||Brief Comments|
|LF Radio||HF Radio||Microwave||Terahertz||Optical/IR||X-rays||Gamma-rays||Gravitational Waves||Neutrinos|
|Other||Magnetars with Low Magnetospheric Twist||Repeat||Mag. reconnection||Curv.||Yes||---||Maybe||Maybe||Maybe||Maybe||Unlikely detectable||---||---||https://arxiv.org/pdf/1904.12036.pdf||Unlikely to form in Galactic magnetars.|
Definitions: LF Radio (3 MHz to 3 GHz); HF Radio (3 GHz to 30 GHz); Microwave (30 to 300 GHz)
FRBs may be created in the closed field line regions of magnetar magnetospheres. Crustal slippage on the surface of the magnetar causes magnetic reconnection and thus particle acceleration, producing coherent emission. To allow emission to escape, the magnetars must have a low-density plasma in the closed field line regions, and hence must have low magnetospheric twist.
Unlikely to form in Galactic magnetars, which have a relatively high magnetospheric twist. Signals above a few MeV are expected to be suppressed by photon splitting and magnetic pair production in the magnetosphere.