Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Using $\bar p p$ and $e^+e^-$ Annihilation Data to Refine Bounds on the
  Baryon-Number-Violating Dinucleon Decays $nn \to e^+e^-$ and $nn \to
  \mu^+\mu^-$   We use $\bar p p$ and $e^+e^-$ annihilation data to further strengthen lower
bounds on the partial lifetimes for the baryon-number-violating dinucleon
decays $nn \to e^+ e^-$ and $nn \to \mu^+\mu^-$.

28
The categories of this paper are: alg-geom
4
The categories of this paper are: cond-mat
6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
16
The categories of this paper are: stat
9
The categories of this paper are: nlin
14
The categories of this paper are: math-ph
10
The categories of this paper are: q-bio
23
The categories of this paper are: solv-int
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
20
The categories of this paper are: acc-phys
27
The categories of this paper are: comp-gas
29
The categories of this paper are: funct-an
25
The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph