Observation of the $B_s^0\to J/\ddot{I}ˆ\ddot{I}•\ddot{I}•$ decay

Abstract

The $B_s^0\to J/\ddot{I}ˆ\ddot{I}•\ddot{I}•$ decay is observed in $pp$ collision data corresponding to an integrated luminosity of 3 fb${}^{-1}$ recorded by the LHCb detector at centre-of-mass energies of 7 TeV and 8 TeV. This is the first observation of this decay channel, with a statistical significance of 15 standard deviations. The mass of the $B_s^0$ meson is measured to be $5367.08\pm 0.38\pm 0.15$ MeV/c${}^2$. The branching fraction ratio $\mathcal{B}(B_s^0\to J/\ddot{I}ˆ\ddot{I}•\ddot{I}•)/\mathcal{B}(B_s^0\to J/\ddot{I}ˆ\ddot{I}•)$ is measured to be $0.0115\pm 0.0012{}_{-0.0009}^{+0.0005}$. In both cases, the first uncertainty is statistical and the second is systematic. No evidence for non-resonant $B_s^0\to J/\ddot{I}ˆ\ddot{I}•K^{+}{K}^{-}$ or $B_s^0\to J/\ddot{I}ˆK^{+}{K}^{-}{K}^{+}{K}^{-}$ decays is found.

All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-033.html