Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Molecular Gas in Candidate Double-Barred Galaxies II. Cooler, Less Dense
  Gas Associated with Stronger Central Concentrations
9
The categories of this paper are: nlin
11
The categories of this paper are: hep-lat
2
The categories of this paper are: math
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys
3
The categories of this paper are: physics
25
The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org
27
The categories of this paper are: comp-gas
22
The categories of this paper are: chao-dyn
14
The categories of this paper are: math-ph
17
The categories of this paper are: q-fin
15
The categories of this paper are: nucl-ex
18
The categories of this paper are: econ