Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Revealing a spiral-shaped molecular cloud in our galaxy - Cloud
  fragmentation under rotation and gravity
24
The categories of this paper are: dg-ga
33
The categories of this paper are: plasm-ph
14
The categories of this paper are: math-ph
35
The categories of this paper are: mtrl-th
21
The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph
19
The categories of this paper are: eess
22
The categories of this paper are: chao-dyn
10
The categories of this paper are: q-bio
23
The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
11
The categories of this paper are: hep-lat
18
The categories of this paper are: econ
17
The categories of this paper are: q-fin
8
The categories of this paper are: hep-ex
34
The categories of this paper are: chem-ph