Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Testing chemical composition of highest energy comic rays   We study basic characteristics of distributions of the depths of shower
maximum in air showers caused by cosmic rays with the highest energies. The
consistency between their average values and widths, and their energy
dependences are discussed within a simple phenomenological model of shower
development independently of assumptions about detailed features of
high--energy interactions. It is shown that reliable information on primary
species can be derived within a partition method. We present examples
demonstrating implications for the changes in mass composition of primary
cosmic rays.

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The categories of this paper are: cs
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The categories of this paper are: nlin
19
The categories of this paper are: eess
12
The categories of this paper are: nucl-th
30
The categories of this paper are: q-alg
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The categories of this paper are: math
5
The categories of this paper are: gr-qc
20
The categories of this paper are: acc-phys
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The categories of this paper are: dg-ga
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The categories of this paper are: q-fin
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The categories of this paper are: physics
27
The categories of this paper are: comp-gas
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The categories of this paper are: math-ph
28
The categories of this paper are: alg-geom
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The categories of this paper are: econ
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The categories of this paper are: hep-th