Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quasi-monoenergetic Laser-Plasma Positron Accelerator using
  Particle-Shower Plasma-Wave interactions   An all-optical centimeter-scale laser-plasma positron accelerator is modeled
to produce quasi-monoenergetic beams with tunable ultra-relativistic energies.
A new principle elucidated here describes the trapping of divergent positrons
that are part of a laser-driven electromagnetic shower with a large energy
spread and their acceleration into a quasi-monoenergetic positron beam in a
laser-driven plasma wave. Proof of this principle using analysis and
Particle-In-Cell simulations demonstrates that, under limits defined here,
existing lasers can accelerate hundreds of MeV pC quasi-monoenergetic positron
bunches. By providing an affordable alternative to kilometer-scale
radio-frequency accelerators, this compact positron accelerator opens up new
avenues of research.

19
The categories of this paper are: eess
1
The categories of this paper are: cs
16
The categories of this paper are: stat
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The categories of this paper are: econ
2
The categories of this paper are: math
12
The categories of this paper are: nucl-th
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The categories of this paper are: adap-org
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The categories of this paper are: cmp-lg
10
The categories of this paper are: q-bio
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The categories of this paper are: quant-ph
8
The categories of this paper are: hep-ex
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The categories of this paper are: q-fin
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The categories of this paper are: dg-ga
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The categories of this paper are: bayes-an
31
The categories of this paper are: ao-sci
0
The categories of this paper are: hep-ph