Pulsar Wind Bubble

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Summary Table
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
SNR (Pulsars) Pulsar Wind Bubble (NS and MWD) Single -- Synch. Yes -- -- -- -- ULXs -- -- -- http://adsabs.harvard.edu/abs/2017MNRAS.467.3542M Emission from the PWN as it expands outwards might be detected in the NS scenario. A SN a few years prior to the FRB may be observed for either body.

Definitions: LF Radio (3 MHz to 3 GHz); HF Radio (3 GHz to 30 GHz); Microwave (30 to 300 GHz)

Model Description

Consider a pulsar (NS or magnetic WD, hereafter MWD) within a nebula. The dissipation of spin energy drives a wind of relativistic electron-positron plasma--a pulsar wind nebula (PWN)--observable as a shell around the NS. Where the plasma wind ceases is called the termination shock. Here the plasma decelerates to sub-relativistic speeds and forms a wind bubble around the pulsar. A subsequent outburst, possibly triggered by pulsar spin-down or by magnetic dissipation in the magnetosphere, will rapidly decelerate when it impacts the PWN, triggering a GRB. Energy that is not radiated away by the explosion itself travels outwards at a relativistic speed, causing a highly relativistic shock wave to propagates forward into space. Synchrotron emission is generated, however the coherence mechanism to generate FRBs at this point is unknown. A synchrotron maser might result from the coherently reflected particles in the shock front, but for NSs and magnetic MWDs the frequency is likely too low to be consistent with FRBs. A reverse shock wave may give rise to afterglow, however both this afterglow and the GRB formed at the shock front are not expected to be observable.

Observational Constraints