Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Probing QCD (media) with prompt photons   The QCD phenomenology of prompt photon production from e-p to p-p/p-pbar and
A-A collisions is reviewed. The use of prompt photons as a probe of (i) parton
distribution functions (in a proton or in nuclei) as well as (ii) fragmentation
functions (into photons and hadrons) and their medium-modifications is
highlighted.

23
The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
2
The categories of this paper are: math
1
The categories of this paper are: cs
30
The categories of this paper are: q-alg
13
The categories of this paper are: quant-ph
6
The categories of this paper are: astro-ph
21
The categories of this paper are: adap-org
7
The categories of this paper are: hep-th
5
The categories of this paper are: gr-qc
19
The categories of this paper are: eess
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The categories of this paper are: dg-ga
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
25
The categories of this paper are: patt-sol
34
The categories of this paper are: chem-ph