Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Dirac Particle in an Aharonov-Bohm Potential: The Structure of the First
  Order S-matrix
25
The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
10
The categories of this paper are: q-bio
27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
23
The categories of this paper are: solv-int
17
The categories of this paper are: q-fin
26
The categories of this paper are: bayes-an
9
The categories of this paper are: nlin
15
The categories of this paper are: nucl-ex
18
The categories of this paper are: econ
29
The categories of this paper are: funct-an
1
The categories of this paper are: cs
6
The categories of this paper are: astro-ph
12
The categories of this paper are: nucl-th