Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Low-Frequency Carbon Recombination Lines in the Orion Molecular Cloud
  Complex
35
The categories of this paper are: mtrl-th
18
The categories of this paper are: econ
34
The categories of this paper are: chem-ph
22
The categories of this paper are: chao-dyn
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
3
The categories of this paper are: physics
7
The categories of this paper are: hep-th
0
The categories of this paper are: hep-ph
26
The categories of this paper are: bayes-an
19
The categories of this paper are: eess
14
The categories of this paper are: math-ph
1
The categories of this paper are: cs
5
The categories of this paper are: gr-qc
27
The categories of this paper are: comp-gas