Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Proton/pion ratios and radial flow in pp and peripheral heavy ion
  collisions
30
The categories of this paper are: q-alg
17
The categories of this paper are: q-fin
13
The categories of this paper are: quant-ph
36
The categories of this paper are: cmp-lg
14
The categories of this paper are: math-ph
18
The categories of this paper are: econ
10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
31
The categories of this paper are: ao-sci
23
The categories of this paper are: solv-int
22
The categories of this paper are: chao-dyn
16
The categories of this paper are: stat
21
The categories of this paper are: adap-org
25
The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con