Free electron laser in magnetars/Fast Radio Bursts

Maxim Lyutikov

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arXiv · 2006.16029

Free electron laser in magnetars/Fast Radio Bursts

Maxim Lyutikov

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Abstract

We discuss coherent free electron laser (FEL) operating during explosive reconnection events in magnetized pair plasma of magnetar magnetospheres. The model explains many salient features of Fast Radio Bursts/magnetars' radio emission: temporal coincidence of radio and high energy bursts, high efficiency of conversion of plasma kinetic energy into coherent radiation, presence of variable, narrow-band emission features drifting down in frequency, high degree of linear polarization. The model relies on magnetar-specific drifting $e^\pm$ plasma components (which generate wiggler field due to the development of the firehose instability) and the presence of reconnection-generated particle beam with mild Lorentz factor of $γ_b \sim$ few hundred.

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Maxim Lyutikov. 2020-06-29. Free electron laser in magnetars/Fast Radio Bursts. https://arxiv.org/abs/2006.16029

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