Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Gamma-ray halos around pulsars as the key to understanding cosmic ray
  transport in the Galaxy
12
The categories of this paper are: nucl-th
35
The categories of this paper are: mtrl-th
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
30
The categories of this paper are: q-alg
3
The categories of this paper are: physics
26
The categories of this paper are: bayes-an
24
The categories of this paper are: dg-ga
4
The categories of this paper are: cond-mat
21
The categories of this paper are: adap-org
20
The categories of this paper are: acc-phys
31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph
18
The categories of this paper are: econ
5
The categories of this paper are: gr-qc