Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Pulsar PSR B0656+14, the Monogem Ring, and the Origin of the `Knee' in
  the Primary Cosmic Ray Spectrum
30
The categories of this paper are: q-alg
12
The categories of this paper are: nucl-th
21
The categories of this paper are: adap-org
34
The categories of this paper are: chem-ph
33
The categories of this paper are: plasm-ph
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
28
The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
26
The categories of this paper are: bayes-an
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
27
The categories of this paper are: comp-gas
9
The categories of this paper are: nlin
1
The categories of this paper are: cs