Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Neutrino processes $\nu \bar\nu \to e^- e^+$ and $\nu \to \nu e^- e^+$
  in a strong magnetic field   The processes of neutrino production of electron-positron pairs, $\nu \bar\nu
\to e^- e^+$ and $\nu \to \nu e^- e^+$, in a magnetic field of arbitrary
strength, where electrons and positrons can be created in the states
corresponding to excited Landau levels, are analysed. The results can be
applied for calculating the efficiency of the electron-positron plasma
production by neutrinos in the conditions of the Kerr black hole accretion disc
considered by experts as the most possible source of a short cosmological gamma
burst.

33
The categories of this paper are: plasm-ph
17
The categories of this paper are: q-fin
16
The categories of this paper are: stat
25
The categories of this paper are: patt-sol
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
8
The categories of this paper are: hep-ex
23
The categories of this paper are: solv-int
26
The categories of this paper are: bayes-an
32
The categories of this paper are: atom-ph
14
The categories of this paper are: math-ph
7
The categories of this paper are: hep-th
29
The categories of this paper are: funct-an
6
The categories of this paper are: astro-ph
30
The categories of this paper are: q-alg