Evidence for the decay $B_c^+ \rightarrow J/ψ3π^+ 2π^-$

Abstract

Evidence is presented for the decay $B_c+\rightarrow J/ψ3π^+2π^-$ 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 $B_c^+\rightarrow J/ψ3π^+ 2π^-$ decay to that of the $B_c^+ \rightarrow J/ψπ^+$ decay is measured to be $$ \frac{Br (B_c^+ \rightarrow J/ψ3π^+2π^)}{Br (B_c^+ \rightarrow J/ψπ^+)} = 1.74\pm0.44\pm0.24, $$ where the first uncertainty is statistical and the second is systematic.

12 pages, 3 figures