Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Free electron laser in magnetars/Fast Radio Bursts   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 $\gamma_b \sim$ few hundred.

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The categories of this paper are: hep-lat
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The categories of this paper are: patt-sol
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The categories of this paper are: econ
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The categories of this paper are: dg-ga
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The categories of this paper are: chem-ph
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The categories of this paper are: math-ph
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The categories of this paper are: nlin
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The categories of this paper are: eess
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The categories of this paper are: alg-geom
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The categories of this paper are: cmp-lg
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The categories of this paper are: math
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The categories of this paper are: atom-ph
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The categories of this paper are: q-alg
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The categories of this paper are: adap-org
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The categories of this paper are: acc-phys
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The categories of this paper are: comp-gas