Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the treatment of $NN$ interaction effects in meson production in $NN$
  collisions   We clarify under what circumstances the nucleon--nucleon final state
interaction fixes the energy dependence of the total cross--section for the
reaction $NN \to NNx$ close to production threshold, where $x$ can be any meson
whose interaction with the nucleon is not too strong. We strongly criticize the
procedure used recently by several authors to include the final state
interaction in the reactions under discussion. In addition, we give a formula
that allows one to estimate the effect of the initial state interaction for the
production of heavy mesons.

19
The categories of this paper are: eess
26
The categories of this paper are: bayes-an
33
The categories of this paper are: plasm-ph
29
The categories of this paper are: funct-an
25
The categories of this paper are: patt-sol
22
The categories of this paper are: chao-dyn
6
The categories of this paper are: astro-ph
24
The categories of this paper are: dg-ga
28
The categories of this paper are: alg-geom
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ
17
The categories of this paper are: q-fin
8
The categories of this paper are: hep-ex
7
The categories of this paper are: hep-th
32
The categories of this paper are: atom-ph
10
The categories of this paper are: q-bio