Study of $B_c^{+}$ meson decays to charmonia plus multihadron final states

Abstract

Four decay modes of the $B_c^{+}$ meson into a $J/\ddot{I}ˆ$ meson and multiple charged kaons or pions are studied using proton-proton collision data, collected with the~LHCb detector at centre-of-mass energies of 7, 8, and 13~TeV and corresponding to an integrated luminosity of $9$~fb${}^{-1}$. The decay $B_c^{+}\to J/\ddot{I}ˆK^{+}{K}^{-}\ddot{I}{€}^{+}\ddot{I}{€}^{+}\ddot{I}{€}^{-}$ is observed for the first time, and evidence for the $B_c^{+}\to J/\ddot{I}ˆ4\ddot{I}{€}^{+}3\ddot{I}{€}^{-}$ decay is found. The decay $B_c^{+}\to J/\ddot{I}ˆ3\ddot{I}{€}^{+}2\ddot{I}{€}^{-}$ is observedand and the previous observation of the $B_c^{+}\to \ddot{I}ˆ(2S)\ddot{I}{€}^{+}\ddot{I}{€}^{+}\ddot{I}{€}^{-}$ decay is confirmed using the $\ddot{I}ˆ(2S)\to J/\ddot{I}ˆ\ddot{I}{€}^{+}\ddot{I}{€}^{-}$ decay mode. Ratios of the branching fractions of these four $B_c^{+}$ decay channels are measured.

18 pages, 6 figures. All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-025.html (LHCb public pages)