Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The influence of the spin-flip transitions on the photon spectrum from
  ultra-relatiovistic electrons in the field of a crystal   We investigate the influence of the spin-flip transitions on formation of the
spectral distribution of the radiation emitted by tens to hundreds GeV
ultrarelativistic electrons incident along crystallographic axis in a thin
single crystal. Both the formalism and the numerical data are presented. The
calculated spectra for 35 to 243 GeV electrons in W crystal are compared with
the dependences obtained experimentally (Kirshenbom K et al 2001 Phys.Rev.Lett
87 054801).

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The categories of this paper are: chem-ph
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The categories of this paper are: q-alg
9
The categories of this paper are: nlin
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The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
16
The categories of this paper are: stat
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The categories of this paper are: q-fin
5
The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio
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The categories of this paper are: quant-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: chao-dyn
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The categories of this paper are: acc-phys
2
The categories of this paper are: math
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The categories of this paper are: cmp-lg
8
The categories of this paper are: hep-ex