出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：A search for the Bs ! μ+μ− and Bd ! μ+μ− decays is presented using 300 pb−1 of pp collisions at p s = 7 TeV collected by the LHCb experiment at the Large Hadron Collider at CERN. The measured upper limit for the branching ratio of the Bs ! μ+μ− decay is B(Bs ! μ+μ−)< 1.3 (1.6)×10−8 at 90% (95 %) confidence level (CL), while in the case of the Bd ! μ+μ− decay the measured upper limit is B(Bd !μ+μ−)< 4.2 (5.1)×10−9 at 90% (95 %) CL. A combination with the 2010 dataset results inB(Bs!μ+μ−)<1.2 (1.5)×10−8 at 90% (95 %) CL.
