Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Neutral iron line in the supernova remnant IC 443 and implications for
  MeV cosmic rays
7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph
12
The categories of this paper are: nucl-th
13
The categories of this paper are: quant-ph
24
The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc
20
The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th
32
The categories of this paper are: atom-ph
21
The categories of this paper are: adap-org
3
The categories of this paper are: physics
19
The categories of this paper are: eess
23
The categories of this paper are: solv-int
27
The categories of this paper are: comp-gas
1
The categories of this paper are: cs
16
The categories of this paper are: stat