Evidence for the decay B⁺_c → J/ψ3π⁺2π^-

Evidence is presented for the decay B⁺ _c → J/ψ3π⁺2π^- using proton-proton collision data, corresponding to an integrated luminosity of 3 fb⁻¹, collected with the LHCb detector. A signal yield of 32 ± 8 decays is found with a significance of 4.5 standard deviations. The ratio of the branching fraction of the B⁺ _c → J/ψ3π⁺2π^- decay to that of the B⁺ _c → J/ψ3π⁺ decay is measured to be (Formula Presented) where the first uncertainty is statistical and the second is systematic.