Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Rapid Formation of Supermassive Black Hole Binaries in Galaxy Mergers
  with Gas
15
The categories of this paper are: nucl-ex
19
The categories of this paper are: eess
27
The categories of this paper are: comp-gas
2
The categories of this paper are: math
16
The categories of this paper are: stat
25
The categories of this paper are: patt-sol
26
The categories of this paper are: bayes-an
20
The categories of this paper are: acc-phys
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
1
The categories of this paper are: cs
3
The categories of this paper are: physics
37
The categories of this paper are: supr-con
4
The categories of this paper are: cond-mat
5
The categories of this paper are: gr-qc
12
The categories of this paper are: nucl-th