Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Direct photons at low transverse momentum -- a QGP signal in pp
  collisions at LHC   We investigate photon production in a scenario of quark-gluon plasma
formation in proton-proton scattering at 7 TeV. It is shown that thermal photon
yields increase quadratically with the charged particle multiplicity. This
gives an enhanced weight to high multiplicity events, and leads to an important
photon production even in minimum bias events, where the thermal photons
largely dominate over the prompt ones at transverse momentum values smaller
than 10 GeV/c.

31
The categories of this paper are: ao-sci
14
The categories of this paper are: math-ph
6
The categories of this paper are: astro-ph
1
The categories of this paper are: cs
29
The categories of this paper are: funct-an
18
The categories of this paper are: econ
17
The categories of this paper are: q-fin
19
The categories of this paper are: eess
24
The categories of this paper are: dg-ga
2
The categories of this paper are: math
13
The categories of this paper are: quant-ph
10
The categories of this paper are: q-bio
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
15
The categories of this paper are: nucl-ex
11
The categories of this paper are: hep-lat