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arXiv · 2403.11352

Observation of the J/$\psi$ $\to$ $\mu^+\mu^-\mu^+\mu^-$ decay in proton-proton collisions at $\sqrt{s}$ = 13 TeV

CMS Collaboration
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Abstract

The J/$\psi$ $\to$ $\mu^+\mu^-\mu^+\mu^-$ decay has been observed with a statistical significance in excess of five standard deviations. The analysis is based on an event sample of proton-proton collisions at a center-of-mass energy of 13 TeV, collected by the CMS experiment in 2018 and corresponding to an integrated luminosity of 33.6 fb$^{-1}$. Normalizing to the J/$\psi$ $\to$ $\mu^+\mu^-$ decay mode leads to a branching fraction [10.1 $^{+3.3}_{-2.7}$ (stat) $\pm$ 0.4 (syst)] $\times$ 10$^{-7}$, a value that is consistent with the standard model prediction.

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CMS Collaboration. 2024-03-17. Observation of the J/$\psi$ $\to$ $\mu^+\mu^-\mu^+\mu^-$ decay in proton-proton collisions at $\sqrt{s}$ = 13 TeV. https://doi.org/10.1103/physrevd.109.l111101

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