Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Major Mergers Host the Most Luminous Red Quasars at z ~ 2: A Hubble
  Space Telescope WFC3/IR Study
31
The categories of this paper are: ao-sci
28
The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org
18
The categories of this paper are: econ
32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
15
The categories of this paper are: nucl-ex
4
The categories of this paper are: cond-mat
11
The categories of this paper are: hep-lat
5
The categories of this paper are: gr-qc
2
The categories of this paper are: math
13
The categories of this paper are: quant-ph
17
The categories of this paper are: q-fin
37
The categories of this paper are: supr-con
25
The categories of this paper are: patt-sol
9
The categories of this paper are: nlin