Evidence for the decay $B_c^+ \\rightarrow J/\\psi 3\\pi^+ 2\\pi^-$

Abstract

Evidence is presented for the decay $B_c+\\rightarrow J/\\psi 3\\pi^+2\\pi^-$ using proton-proton collision data, corresponding to an integrated luminosity of 3fb$^{-1}$, collected with the LHCb detector. A signal yield of $32\\pm8$ decays is found with a significance of 4.5 standard deviations. The ratio of the branching fraction of the $B_c^+\\rightarrow J/\\psi 3\\pi^+ 2\\pi^-$ decay to that of the $B_c^+ \\rightarrow J/\\psi \\pi^+$ decay is measured to be $$ \\frac{Br (B_c^+ \\rightarrow J/\\psi 3\\pi^+2\\pi^)}{Br (B_c^+ \\rightarrow J/\\psi \\pi^+)} = 1.74\\pm0.44\\pm0.24, $$ where the first uncertainty is statistical and the second is systematic.