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Title: Can a Strong Radio Burst Escape the Magnetosphere of a Magnetar?
Abstract

We examine the possibility that fast radio bursts (FRBs) are emitted inside the magnetosphere of a magnetar. On its way out, the radio wave must interact with a low-densitye±plasma in the outer magnetosphere at radiiR= 109–1010cm. In this region, the magnetospheric particles have a huge cross section for scattering the wave. As a result, the wave strongly interacts with the magnetosphere and compresses it, depositing the FRB energy into the compressed field and the scattered radiation. The scattered spectrum extends to theγ-ray band and triggerse±avalanche, further boosting the opacity. These processes choke FRBs, disfavoring scenarios with a radio source confined atR≪ 1010cm. Observed FRBs can be emitted by magnetospheric flare ejecta transporting energy to large radii.

 
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Award ID(s):
2009453
NSF-PAR ID:
10305468
Author(s) / Creator(s):
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astrophysical Journal Letters
Volume:
922
Issue:
1
ISSN:
2041-8205
Format(s):
Medium: X Size: Article No. L7
Size(s):
["Article No. L7"]
Sponsoring Org:
National Science Foundation
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