Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Polarized synchrotron radiation from the Andromeda Galaxy M31 and
  background sources at 350 MHz
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
30
The categories of this paper are: q-alg
3
The categories of this paper are: physics
34
The categories of this paper are: chem-ph
28
The categories of this paper are: alg-geom
37
The categories of this paper are: supr-con
23
The categories of this paper are: solv-int
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
4
The categories of this paper are: cond-mat
10
The categories of this paper are: q-bio
11
The categories of this paper are: hep-lat
14
The categories of this paper are: math-ph