Abellan Beteta, CarlosCalvo Gómez, MíriamCamboni, AlessandroComerma Montells, AlbertDomingo Bonal, FrancescGarrido Beltrán, LluísGascón Fora, DavidGrabalosa Gándara, MarcGraciani Díaz, RicardoGraugés Pous, EugeniLópez Asamar, EliasPérez-Calero Yzquierdo, AntonioPicatoste Olloqui, EduardoPie Valls, B. (Blai)Potterat, CédricPuig Navarro, AlbertRoselló, M.Ruiz, Hugo (Ruiz Pérez)Vázquez Gómez, RicardVilasis-Cardona, XavierLHCb Collaboration2019-05-222019-05-222012-06-050031-9007https://hdl.handle.net/2445/133691A search for B 0 s → μ + μ − and B 0 → μ + μ − decays is performed using 1.0     fb − 1 of p p collision data collected at √ s = 7     TeV with the LHCb experiment at the Large Hadron Collider. For both decays, the number of observed events is consistent with expectation from background and standard model signal predictions. Upper limits on the branching fractions are determined to be B ( B 0 s → μ + μ − ) < 4.5 ( 3.8 ) × 10 − 9 and B ( B 0 → μ + μ − ) < 1.0 ( 0.81 ) × 10 − 9 at 95% (90%) confidence level.8 p.application/pdfengcc by (c) CERN; LHCb Collaboration, 2012http://creativecommons.org/licenses/by/3.0/es/Física de partículesExperimentsParticle physicsExperimentsinfo:eu-repo/semantics/article6189752019-05-22info:eu-repo/semantics/openAccess