Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Shape effects in nonlinear Thomson and Compton processes: the quest for
  MeV high-order harmonics   Spectra of Thomson and Compton radiation, emitted during electron scattering
off an intense laser beam, are calculated using the frameworks of classical and
strong-field quantum electrodynamics, respectively. Both approaches use a
plane-wave-fronted pulse approximation regarding the driving laser beam. Within
this approximation, a very good agreement between Thomson and Compton frequency
distributions is observed provided that frequencies of the emitted radiation is
relatively low. The dependence of frequency spectra on the laser pulse envelope
is analyzed. This becomes important in the context of ultra-short pulse
generation, as illustrated by numerical examples.

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The categories of this paper are: quant-ph
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The categories of this paper are: eess
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The categories of this paper are: comp-gas
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The categories of this paper are: chao-dyn
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The categories of this paper are: ao-sci
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The categories of this paper are: hep-lat
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The categories of this paper are: atom-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: alg-geom
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The categories of this paper are: bayes-an
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The categories of this paper are: astro-ph
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The categories of this paper are: solv-int
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The categories of this paper are: plasm-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: q-alg
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The categories of this paper are: acc-phys