First observation of the decay
arXiv:1210.2645 · doi:10.1007/JHEP12(2012)125
Abstract
A discovery of the rare decay is presented. This decay is observed for the first time, with 5.2 significance. The observation is made using collision data, corresponding to an integrated luminosity of 1.0 fb, collected with the LHCb detector. The measured branching fraction is (2.3 0.6 (stat.) 0.1 (syst.)), and the ratio of the and $B^{+} \rightarrow \K^{+} μ^{+} μ^{-}$ branching fractions is measured to be 0.053 0.014 (stat.) 0.001 (syst.).
20 pages (including authorlist), 8 figures. Version published in JHEP