Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Multifrequency study of HH 137 and HH 138: Discovering new knots and
  molecular outflows with Gemini and APEX
16
The categories of this paper are: stat
29
The categories of this paper are: funct-an
2
The categories of this paper are: math
34
The categories of this paper are: chem-ph
15
The categories of this paper are: nucl-ex
20
The categories of this paper are: acc-phys
32
The categories of this paper are: atom-ph
0
The categories of this paper are: hep-ph
18
The categories of this paper are: econ
22
The categories of this paper are: chao-dyn
11
The categories of this paper are: hep-lat
37
The categories of this paper are: supr-con
9
The categories of this paper are: nlin
31
The categories of this paper are: ao-sci
27
The categories of this paper are: comp-gas
30
The categories of this paper are: q-alg