Observation of B+ → J/ψ 3π ^+ 2π ^- and B ^+ → ψ (2S) π ^+ π ^+ π ^- decays

Abstract

The decays B ^+ → J/ψ 3π ^+ 2π ^- and B ^+ → ψ (2S) π ^+ π ^+ π ^- are observed for the first time using a data sample corresponding to an integrated luminosity of 3.0 fb^-1, collected by the LHCb experiment in proton-proton collisions at the centre-of-mass energies of 7 and 8 TeV. The branching fractions relative to that of B ^+ → ψ (2S) K ^+ are measured to be dfrac B ( B ^+ → J/ψ 3π ^+ 2π ^- )B ( B ^+ → ψ (2S) K ^+ )= & ( 1.88± 0.17± 0.09)× 10^-2, dfrac B ( B ^+ → ψ (2S) π ^+ π ^+ π ^- )B ( B ^+ → ψ (2S) K ^+ )= & ( 3.04± 0.50± 0.26)× 10^-2, where the first uncertainties are statistical and the second are systematic.