Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: The X-ray Luminosity Function of "The Antennae" Galaxies (NGC4038/39)
  and the Nature of Ultra-Luminous X-ray Sources
9
The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio
37
The categories of this paper are: supr-con
21
The categories of this paper are: adap-org
31
The categories of this paper are: ao-sci
32
The categories of this paper are: atom-ph
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
26
The categories of this paper are: bayes-an
29
The categories of this paper are: funct-an
12
The categories of this paper are: nucl-th
2
The categories of this paper are: math
19
The categories of this paper are: eess
23
The categories of this paper are: solv-int
22
The categories of this paper are: chao-dyn