Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Collinear QCD Models   The small momentum fraction x behaviour of quarks in mesons is analysed in
the 1+1-dimensional reduced model of large-N QCD by light-cone quantisation.

32
The categories of this paper are: atom-ph
10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
1
The categories of this paper are: cs
37
The categories of this paper are: supr-con
17
The categories of this paper are: q-fin
18
The categories of this paper are: econ
31
The categories of this paper are: ao-sci
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
4
The categories of this paper are: cond-mat
23
The categories of this paper are: solv-int
26
The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph