Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Diagnostic Techniques for Particle-in-Cell Simulations of Laser-produced
  Gamma-rays in the Strong-field QED Regime   The emission of multi-MeV ($\gamma$-ray) photons from the interaction of a
high-powered laser pulse with a dense plasma target is studied using
particle-in-cell simulations. A new set of diagnostic techniques is presented
and applied to analyze the intense field and ultra-relativistic electrons. Such
methods elucidate the dominant processes responsible for efficient
laser-to-$\gamma$ energy conversion, which include nonlinear Compton scattering
and magneto-bremsstrahlung radiation, and provide a clear picture of the
interaction on a microscopic level. We identify regions in the plasma target of
high photon energy-density and obtain an energy conversion efficiency as high
as 30%. The essential characteristics of the interaction are validated with
full-3D simulations.

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The categories of this paper are: gr-qc
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The categories of this paper are: adap-org
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The categories of this paper are: astro-ph
20
The categories of this paper are: acc-phys
27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
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The categories of this paper are: hep-ex
0
The categories of this paper are: hep-ph
31
The categories of this paper are: ao-sci
14
The categories of this paper are: math-ph
34
The categories of this paper are: chem-ph
12
The categories of this paper are: nucl-th
33
The categories of this paper are: plasm-ph
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The categories of this paper are: hep-th
24
The categories of this paper are: dg-ga
15
The categories of this paper are: nucl-ex