NS Combing

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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
Other NS Combing Both Various Mag. reconnection Yes -- -- -- -- -- -- -- -- http://adsabs.harvard.edu/abs/2017ApJ...836L..32Z, http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1801.05436 The model can apply to a variety of events, and thus counterparts will depend on the scenario.

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


Model Description

Cosmic combing is the process in which the field lines of a NS's magnetosphere are swept out in a stream by a strong plasma. The effect is caused by ram pressure: the bulk resistance of a fluid acting on an object. When this pressure is greater than the magnetic field pressure, the drag will comb the magnetic field in a different direction, causing reconnection with emission consistent with an FRB . Combing may occur in a variety of situations, such as: a GRB, a SN, an AGN flare, or a stellar flare. As such, it is a difficult theory to test in general, however a specific scenario has been considered: the combing of a pulsar by an accreting SMBH. An FRB would be observable for half of the pulsar's orbital period around the SMBH, implying the signal is periodic. This periodicity would not be perfect - the SMBH wind that initiates FRBs is variable and thus FRB signals are sporadic. The RM should vary with orbital periodicity, but this would be more difficult to confirm given the sporadic FRB emission. Finally, the polarization angle of each burst within an orbital period would vary depending on the phase of the pulsar's orbit, and should be correlated with the varying RM.

Observational Constraints

To be filled in with updated draft