Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Study of the PYTHIA $\Delta\eta\Delta\phi$ correlation as a function of
  multiplicity and transverse sphericity in proton-proton collisions at 7 TeV
30
The categories of this paper are: q-alg
7
The categories of this paper are: hep-th
9
The categories of this paper are: nlin
33
The categories of this paper are: plasm-ph
17
The categories of this paper are: q-fin
35
The categories of this paper are: mtrl-th
5
The categories of this paper are: gr-qc
27
The categories of this paper are: comp-gas
25
The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph
13
The categories of this paper are: quant-ph
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
19
The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs