Study of Bc+→χcπ+ decays
A study of Bc+→χcπ+ decays is reported using proton-proton collision data, collected with the LHCb detector at centre-of-mass energies of 7, 8, and 13 TeV, corresponding to an integrated luminosity of 9 fb−1. The decay Bc+→χc2π+ is observed for the first time, with a significance exceeding seven standard deviations. The relative branching fraction with respect to the Bc+→J/ψπ+ decay is measured to