Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Determination of the Central Mass in Active Galactic Nuclei Using
  Cross-Correlation Lags and Velocity Dispersions
27
The categories of this paper are: comp-gas
21
The categories of this paper are: adap-org
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th
16
The categories of this paper are: stat
19
The categories of this paper are: eess
22
The categories of this paper are: chao-dyn
23
The categories of this paper are: solv-int
13
The categories of this paper are: quant-ph
2
The categories of this paper are: math
29
The categories of this paper are: funct-an
12
The categories of this paper are: nucl-th
35
The categories of this paper are: mtrl-th
3
The categories of this paper are: physics
5
The categories of this paper are: gr-qc
25
The categories of this paper are: patt-sol