Observation of the decay $B_c \rightarrow J/\psi K^+ K^- \pi^+ $

TL;DR

This paper reports the first observation of the decay B_c → J/ψ K^+ K^- π^+ in proton-proton collisions, measuring its branching ratio relative to B_c → J/ψ π^+ with significant statistical confidence.

Contribution

The first observation of the decay B_c → J/ψ K^+ K^- π^+ and measurement of its branching ratio relative to B_c → J/ψ π^+ are reported.

Findings

78±14 observed decays with 6.2σ significance

Branching ratio of B_c → J/ψ K^+ K^- π^+ to B_c → J/ψ π^+ is 0.53±0.10±0.05

First measurement of this decay mode

Abstract

The decay $B_c\rightarrow J/\psi K^+ K^- \pi^+$ is observed for the first time, using proton-proton collisions collected with the LHCb detector corresponding to an integrated luminosity of 3fb$^{-1}$. A signal yield of $78\pm14$ decays is reported with a significance of 6.2 standard deviations. The ratio of the branching fraction of $\B_c \rightarrow J/\psi K^+ K^- \pi^+$ decays to that of $B_c \rightarrow J/\psi \pi^+$ decays is measured to be $0.53\pm 0.10\pm0.05$, where the first uncertainty is statistical and the second is systematic.