Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Single-Pass Lazer Polarization of Ultrarelativistic Positrons   The new method for producing of the polarized relativistic positrons is
suggested. A beam of unpolarized positrons accelerated up to a few GeV can be
polarized during a head-on collision with an intense circularly polarized lazer
wave. After a multiple Compton backscattering process the initial positrons may
lose a substantial part of its energy and, as consequence, may acquire the
significant longitudinal polarization. The simple formulas for the final
positron energy and polarization degree depended on the laser flash parameters
have been obtained. The comparison of efficiences for the suggested technique
and known ones is carried out. Some advantages of the new method were shown.

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The categories of this paper are: patt-sol
15
The categories of this paper are: nucl-ex
5
The categories of this paper are: gr-qc
23
The categories of this paper are: solv-int
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The categories of this paper are: cmp-lg
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The categories of this paper are: adap-org
10
The categories of this paper are: q-bio
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The categories of this paper are: q-fin
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The categories of this paper are: q-alg
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The categories of this paper are: nlin
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The categories of this paper are: nucl-th
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The categories of this paper are: math
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci
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The categories of this paper are: eess
13
The categories of this paper are: quant-ph