Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Cherenkov radiation by neutrinos   We discuss the Cherenkov process $\nu\to\nu\gamma$ in the presence of a
homogeneous magnetic field. The neutrinos are taken to be massless with only
standard-model couplings. The magnetic field fulfills the dual purpose of
inducing an effective neutrino-photon vertex and of modifying the photon
dispersion relation such that the Cherenkov condition $\omega<|{\bf k}|$ is
fulfilled. For a field strength $B_{\rm crit}=m_e^2/e=4.41\times10^{13} Gauss$
and for $E=2m_e$ the Cherenkov rate is about $6\times10^{-11}s^{-1}$.

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The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
18
The categories of this paper are: econ
21
The categories of this paper are: adap-org
25
The categories of this paper are: patt-sol
33
The categories of this paper are: plasm-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: cond-mat
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The categories of this paper are: bayes-an
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The categories of this paper are: comp-gas
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The categories of this paper are: physics
35
The categories of this paper are: mtrl-th
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The categories of this paper are: supr-con
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The categories of this paper are: hep-lat
34
The categories of this paper are: chem-ph