Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Design studies for a multi-TeV gamma-ray telescope array : PeX (PeV
  eXplorer)
36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
19
The categories of this paper are: eess
2
The categories of this paper are: math
26
The categories of this paper are: bayes-an
7
The categories of this paper are: hep-th
4
The categories of this paper are: cond-mat
3
The categories of this paper are: physics
12
The categories of this paper are: nucl-th
30
The categories of this paper are: q-alg
37
The categories of this paper are: supr-con
33
The categories of this paper are: plasm-ph
15
The categories of this paper are: nucl-ex
24
The categories of this paper are: dg-ga
11
The categories of this paper are: hep-lat
16
The categories of this paper are: stat