Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Collisional deexcitation of exotic hydrogen atoms in highly excited
  states. I. Cross-sections   The deexcitation of exotic hydrogen atoms in highly excited states in
collisions with hydrogen molecules has been studied using the
classical-trajectory Monte Carlo method. The Coulomb transitions with large
change of principal quantum number n have been found to be the dominant
collisional deexcitation mechanism at high n. The molecular structure of the
hydrogen target is shown to be essential for the dominance of transitions with
large \Delta n. The external Auger effect has been studied in the eikonal
approximation. The resulting partial wave cross-sections are consistent with
unitarity and provide a more reliable input for cascade calculations than the
previously used Born approximation.

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The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
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The categories of this paper are: funct-an
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The categories of this paper are: econ
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The categories of this paper are: eess
10
The categories of this paper are: q-bio
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The categories of this paper are: comp-gas
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The categories of this paper are: bayes-an
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The categories of this paper are: solv-int
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The categories of this paper are: ao-sci
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The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
4
The categories of this paper are: cond-mat
33
The categories of this paper are: plasm-ph