Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Shock Excited Maser Emission from the Supernova Remnant W28
31
The categories of this paper are: ao-sci
27
The categories of this paper are: comp-gas
28
The categories of this paper are: alg-geom
12
The categories of this paper are: nucl-th
30
The categories of this paper are: q-alg
11
The categories of this paper are: hep-lat
16
The categories of this paper are: stat
32
The categories of this paper are: atom-ph
22
The categories of this paper are: chao-dyn
24
The categories of this paper are: dg-ga
7
The categories of this paper are: hep-th
4
The categories of this paper are: cond-mat
17
The categories of this paper are: q-fin
35
The categories of this paper are: mtrl-th
14
The categories of this paper are: math-ph
19
The categories of this paper are: eess