Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Systematic variations of central mass density slopes in early-type
  galaxies
19
The categories of this paper are: eess
33
The categories of this paper are: plasm-ph
0
The categories of this paper are: hep-ph
24
The categories of this paper are: dg-ga
14
The categories of this paper are: math-ph
23
The categories of this paper are: solv-int
9
The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
20
The categories of this paper are: acc-phys
2
The categories of this paper are: math
18
The categories of this paper are: econ
21
The categories of this paper are: adap-org
16
The categories of this paper are: stat
13
The categories of this paper are: quant-ph
15
The categories of this paper are: nucl-ex
3
The categories of this paper are: physics