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arXiv · 2108.07881

Can a strong radio burst escape the magnetosphere of a magnetar?

Andrei M. Beloborodov
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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-density $e^\pm$ plasma in the outer magnetosphere at radii $R=10^9$-$10^{10}\,$cm. 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 the $\gamma$-ray band and triggers $e^\pm$ avalanche, further boosting the opacity. These processes choke FRBs, disfavoring scenarios with a radio source confined at $R\ll 10^{10}\,$cm. Observed FRBs can be emitted by magnetospheric flare ejecta transporting energy to large radii.

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Andrei M. Beloborodov. 2021-08-17. Can a strong radio burst escape the magnetosphere of a magnetar?. https://doi.org/10.3847/2041-8213%2Fac2fa0

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