Evidence for the rare decay $\Sigma^+ \to p \mu^+ \mu^-$ at LHCb

TL;DR

This paper reports evidence for the rare decay $ ext{Σ}^+ o p ext{μ}^+ ext{μ}^-$ observed at LHCb with a significance of 4.0 standard deviations, based on $pp$ collision data at 7 and 8 TeV.

Contribution

First evidence for the rare decay $ ext{Σ}^+ o p ext{μ}^+ ext{μ}^-$ at LHCb, expanding understanding of hyperon decay modes.

Findings

Observed excess with 4.0 sigma significance

No significant structure in dimuon mass distribution

Analyzed 3 fb$^{-1}$ of data at 7 and 8 TeV

Abstract

A search for the rare decay $\Sigma^+ \to p \mu^+ \mu^-$ is performed using $pp$ collision data recorded by the LHCb experiment at centre-of-mass energies $\sqrt{s} = 7$ and $8$ TeV, corresponding to an integrated luminosity of $3 fb^{-1}$. An excess of events is observed with respect to the background expectations with a signal significance of 4.0 standard deviations. No significant structure is observed in the dimuon invariant mass distribution.