Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: EAS age determination from the study of the lateral distribution of
  charged particles near the shower axis with the ARGO-YBJ experiment   The ARGO-YBJ experiment, a full coverage extensive air shower (EAS) detector
located at high altitude (4300 m a.s.l.) in Tibet, China, has smoothly taken
data, with very high stability, since November 2007 to the beginning of 2013.
The array consisted of a carpet of about 7000 m$^2$ Resistive Plate Chambers
(RPCs) operated in streamer mode and equipped with both digital and analog
readout, providing the measurement of particle densities up to few particles
per cm$^2$. The unique detector features (full coverage, readout granularity,
wide dynamic range, etc) and location (very high altitude) allowed a detailed
study of the lateral density profile of charged particles at ground very close
to the shower axis and its description by a proper lateral distribution
function (LDF). In particular, the information collected in the first 10 m from
the shower axis have been shown to provide a very effective tool for the
determination of the shower development stage ("age") in the energy range 50
TeV - 10 PeV. The sensitivity of the age parameter to the mass composition of
primary Cosmic Rays is also discussed.

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The categories of this paper are: adap-org
12
The categories of this paper are: nucl-th
36
The categories of this paper are: cmp-lg
19
The categories of this paper are: eess
9
The categories of this paper are: nlin
23
The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
16
The categories of this paper are: stat
18
The categories of this paper are: econ
27
The categories of this paper are: comp-gas
4
The categories of this paper are: cond-mat
32
The categories of this paper are: atom-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: math-ph
29
The categories of this paper are: funct-an