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arXiv · 1910.14566

Testing the HyperCP anomaly at LHCb: evidence for the $\Sigma^+ \to p \mu^+ \mu^-$ decay

Francesco Dettori
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Abstract

A search for $\Sigma^+ \to p \mu^+ \mu^-$ decays with LHCb Run 1 data is presented, yielding an evidence for this decay and a measurement of a branching fraction compatible with the Standard Model. The HyperCP anomaly in the dimuon invariant mass distribution is not confirmed, and its branching fraction central value is excluded at 95\% CL. Prospects for the future of this measurement in LHCb are also presented.

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Francesco Dettori. 2019-10-31. Testing the HyperCP anomaly at LHCb: evidence for the $\Sigma^+ \to p \mu^+ \mu^-$ decay. https://doi.org/10.1088/1742-6596%2F1526%2F1%2F012021

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