Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the angular distribution of extensive air showers   Angular distributions of extensive air showers with different number of
charged particles in the range 2.5x10^5--4x10^7 are derived using the
experimental data obtained with the EAS MSU array. Possible approximations of
the obtained distributions with different empiric functions available in
literature, are analysed. It is shown that the exponential function provides
the best approximation of the angular distributions in the sense of the
chi-squared criterion.

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The categories of this paper are: adap-org
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The categories of this paper are: eess
28
The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
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The categories of this paper are: mtrl-th
3
The categories of this paper are: physics
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin
27
The categories of this paper are: comp-gas
8
The categories of this paper are: hep-ex
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The categories of this paper are: bayes-an
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The categories of this paper are: patt-sol
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The categories of this paper are: solv-int
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The categories of this paper are: math-ph
18
The categories of this paper are: econ
29
The categories of this paper are: funct-an