Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Electron-ion coupling upstream of relativistic collisionless shocks   It is argued and demonstrated by particle-in-cell simulations that the
synchrotron maser instability could develop at the front of a relativistic,
magnetized shock. The instability generates strong low-frequency
electromagnetic waves propagating both upstream and downstream of the shock.
Upstream of the shock, these waves make electrons lag behind ions so that a
longitudinal electric field arises and the electrons are accelerated up to the
ion kinetic energy. Then thermalization at the shock front results in a plasma
with equal temperatures of electrons and ions. Downstream of the shock, the
amplitude of the maser-generated wave may exceed the strength of the
shock-compressed background magnetic field. In this case the shock-accelerated
particles radiate via nonlinear Compton scattering rather than via a
synchrotron mechanism. The spectrum of the radiation differs, in the
low-frequency band, from that of the synchrotron radiation, providing possible
observational tests of the model.

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The categories of this paper are: q-alg
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The categories of this paper are: dg-ga
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The categories of this paper are: math-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: eess
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The categories of this paper are: acc-phys
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The categories of this paper are: gr-qc
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The categories of this paper are: cond-mat
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The categories of this paper are: adap-org
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The categories of this paper are: hep-lat
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The categories of this paper are: nucl-ex
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The categories of this paper are: supr-con
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The categories of this paper are: q-bio
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The categories of this paper are: nlin
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The categories of this paper are: cmp-lg
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The categories of this paper are: nucl-th