Alfonso Albero, AlejandroCalvo Gómez, MíriamCamboni, AlessandroCoquereau, SamuelGarrido Beltrán, LluísGascón Fora, DavidGraciani Díaz, RicardoGraugés Pous, EugeniMarin Benito, CarlaLHCb Collaboration2022-05-042022-05-0420181126-6708https://hdl.handle.net/2445/185384Abstract: A search for the decay B0 s → K ∗0 µ +µ − is presented using data sets corresponding to 1.0, 2.0 and 1.6 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 B0 s → K ∗0 µ +µ − decay is determined to be B(B0 s → K ∗0 µ +µ −) = [2.9 ± 1.0 (stat) ± 0.2 (syst) ± 0.3 (norm)] × 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.24 p.application/pdfengcc-by (c) LHCb Collaboration (UB: Alfonso Albero, A. et al., 2018https://creativecommons.org/licenses/by/4.0/HadronsGran Col·lisionador d'HadronsFísica de partículesExperimentsHadronsLarge Hadron Collider (France and Switzerland)Particle physicsExperimentsinfo:eu-repo/semantics/article6846702022-05-04info:eu-repo/semantics/openAccess