Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Observation of the rare $B^0_s\to\mu^+\mu^-$ decay from the combined
  analysis of CMS and LHCb data   A joint measurement is presented of the branching fractions
$B^0_s\to\mu^+\mu^-$ and $B^0\to\mu^+\mu^-$ in proton-proton collisions at the
LHC by the CMS and LHCb experiments. The data samples were collected in 2011 at
a centre-of-mass energy of 7 TeV, and in 2012 at 8 TeV. The combined analysis
produces the first observation of the $B^0_s\to\mu^+\mu^-$ decay, with a
statistical significance exceeding six standard deviations, and the best
measurement of its branching fraction so far. Furthermore, evidence for the
$B^0\to\mu^+\mu^-$ decay is obtained with a statistical significance of three
standard deviations. The branching fraction measurements are statistically
compatible with SM predictions and impose stringent constraints on several
theories beyond the SM.

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The categories of this paper are: patt-sol
5
The categories of this paper are: gr-qc
3
The categories of this paper are: physics
30
The categories of this paper are: q-alg
2
The categories of this paper are: math
29
The categories of this paper are: funct-an
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The categories of this paper are: stat
28
The categories of this paper are: alg-geom
12
The categories of this paper are: nucl-th
4
The categories of this paper are: cond-mat
20
The categories of this paper are: acc-phys
27
The categories of this paper are: comp-gas
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The categories of this paper are: atom-ph
6
The categories of this paper are: astro-ph
11
The categories of this paper are: hep-lat
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The categories of this paper are: solv-int