Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Infall/Expansion Velocities in the Low-Mass Dense Cores L492, L694-2,
  and L1521F: Dependence on Position and Molecular Tracer
8
The categories of this paper are: hep-ex
29
The categories of this paper are: funct-an
37
The categories of this paper are: supr-con
23
The categories of this paper are: solv-int
28
The categories of this paper are: alg-geom
12
The categories of this paper are: nucl-th
3
The categories of this paper are: physics
31
The categories of this paper are: ao-sci
32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
17
The categories of this paper are: q-fin
20
The categories of this paper are: acc-phys
11
The categories of this paper are: hep-lat
4
The categories of this paper are: cond-mat
18
The categories of this paper are: econ
22
The categories of this paper are: chao-dyn