# Evidence for the decay ${B}_S^0\to {\overline{K}}^{\ast 0}{\mu}^{+}{\mu}^{-}$

Peter Clarke, Greig Cowan, Stephan Eisenhardt, Silvia Gambetta, Franz Muheim, Matthew Needham, Stephen Playfer, LHCb Collaboration, Marco Pappagallo

Research output: Contribution to journalArticlepeer-review

## Abstract

A search for the decay $B_{s}^0 \rightarrow \overline{K}{}^{*0}\mu^+\mu^-$ is presented using data sets corresponding to 1.0, 2.0 and 1.6 $\text{fb}^{-1}$ of integrated luminosity collected during $pp$ collisions with the LHCb experiment at centre-of-mass energies of 7, 8 and 13 TeV, respectively. An excess is found over the background-only hypothesis with a significance of 3.4 standard deviations. The branching fraction of the $B_{s}^0 \rightarrow \overline{K}{}^{*0}\mu^+\mu^-$ decay is determined to be $\mathcal{B}(B_{s}^0 \rightarrow \overline{K}{}^{*0}\mu^+\mu^-) = [2.9 \pm 1.0~(\text{stat}) \pm 0.2~(\text{syst}) \pm 0.3~(\text{norm})] \times 10^{-8}$, where the first and second uncertainties are statistical and systematic, respectively. The third uncertainty is due to limited knowledge of external parameters used to normalise the branching fraction measurement.
Original language English 020 Journal of High Energy Physics 1807 3 Jul 2018 https://doi.org/10.1007/JHEP07(2018)020 E-pub ahead of print - 3 Jul 2018