Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Development of Yangbajing Air shower Core detector array for a new EAS
  hybrid Experiment   Aiming at the observation of cosmic-ray chemical composition at the "knee"
energy region, we have been developinga new type air-shower core detector (YAC,
Yangbajing Air shower Core detector array) to be set up at Yangbajing
(90.522$^\circ$ E, 30.102$^\circ$ N, 4300 m above sea level, atmospheric depth:
606 g/m$^2$) in Tibet, China. YAC works together with the Tibet air-shower
array (Tibet-III) and an underground water cherenkov muon detector array (MD)
as a hybrid experiment. Each YAC detector unit consists of lead plates of 3.5
cm thick and a scintillation counter which detects the burst size induced by
high energy particles in the air-shower cores. The burst size can be measured
from 1 MIP (Minimum Ionization Particle) to $10^{6}$ MIPs. The first phase of
this experiment, named "YAC-I", consists of 16 YAC detectors each having the
size 40 cm $\times$ 50 cm and distributing in a grid with an effective area of
10 m$^{2}$. YAC-I is used to check hadronic interaction models. The second
phase of the experiment, called "YAC-II", consists of 124 YAC detectors with
coverage about 500 m$^2$. The inner 100 detectors of 80 cm $\times $ 50 cm each
are deployed in a 10 $\times$ 10 matrix from with a 1.9 m separation and the
outer 24 detectors of 100 cm $\times$ 50 cm each are distributed around them to
reject non-core events whose shower cores are far from the YAC-II array. YAC-II
is used to study the primary cosmic-ray composition, in particular, to obtain
the energy spectra of proton, helium and iron nuclei between 5$\times$$10^{13}$
eV and $10^{16}$ eV covering the "knee" and also being connected with direct
observations at energies around 100 TeV. We present the design and performance
of YAC-II in this paper.

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The categories of this paper are: q-bio
27
The categories of this paper are: comp-gas
29
The categories of this paper are: funct-an
7
The categories of this paper are: hep-th
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
15
The categories of this paper are: nucl-ex
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The categories of this paper are: math
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
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The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
35
The categories of this paper are: mtrl-th
30
The categories of this paper are: q-alg
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The categories of this paper are: dg-ga
36
The categories of this paper are: cmp-lg