Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: GRB 180418A: A possibly-short GRB with a wide-angle outflow in a faint
  host galaxy
8
The categories of this paper are: hep-ex
7
The categories of this paper are: hep-th
12
The categories of this paper are: nucl-th
22
The categories of this paper are: chao-dyn
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
27
The categories of this paper are: comp-gas
2
The categories of this paper are: math
24
The categories of this paper are: dg-ga
16
The categories of this paper are: stat
13
The categories of this paper are: quant-ph
28
The categories of this paper are: alg-geom
3
The categories of this paper are: physics
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg