Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Scattering processes in antiprotonic hydrogen - hydrogen atom collisions   The elastic scattering, Stark transitions and Coulomb deexcitation of excited
antiprotonic hydrogen atom in collisions with hydrogenic atom have been studied
in the framework of the fully quantum-mechanical close-coupling method for the
first time. The total cross sections $\sigma_{nl \to n'l'}(E)$ and averaged on
the initial angular momentum $l$ cross sections $\sigma_{n\to n'}(E)$ have been
calculated for the initial states of $(\bar{p}p)_{n}$ atoms with the principal
quantum number $n=3 - 14 $ and at the relative energies $E=0.05 - 50$ eV. The
energy shifts of the $ns$ states due to the strong interaction and relativistic
effects are taken into account. Some of our results are compared with the
semiclassical calculations.

33
The categories of this paper are: plasm-ph
21
The categories of this paper are: adap-org
11
The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
18
The categories of this paper are: econ
24
The categories of this paper are: dg-ga
26
The categories of this paper are: bayes-an
13
The categories of this paper are: quant-ph
3
The categories of this paper are: physics
4
The categories of this paper are: cond-mat
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn
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The categories of this paper are: comp-gas
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The categories of this paper are: cmp-lg
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The categories of this paper are: q-alg
16
The categories of this paper are: stat