Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: $A_N$ at small negative values of $\xf$ in the reaction $p+p(pol) \to
  \pi^0+X$ at 70 GeV and universal threshold in inclusive pion production
7
The categories of this paper are: hep-th
5
The categories of this paper are: gr-qc
6
The categories of this paper are: astro-ph
25
The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas
21
The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph
15
The categories of this paper are: nucl-ex
10
The categories of this paper are: q-bio
24
The categories of this paper are: dg-ga
11
The categories of this paper are: hep-lat
4
The categories of this paper are: cond-mat
19
The categories of this paper are: eess
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
36
The categories of this paper are: cmp-lg