Experimental study of ${\ensuremath{\psi}}^{\ensuremath{'}}$ decays to ${K}^{+}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}$ and ${K}^{+}{K}^{\ensuremath{-}}\ensuremath{\eta}$

Experimental study of $ψ^{'}$ decays to $K^{+} K^{-} π^{0}$ and $K^{+} K^{-} η$

M. Ablikim et al. (BESIII Collaboration)

Phys. Rev. D 86, 072011 – Published 26 October 2012

Abstract

Using $(106 \pm 4) \times 10^{6}$ $ψ^{'}$ events accumulated with the BESIII detector at the BEPCII $e^{+} e^{-}$ collider, we present measurements of the branching fractions for $ψ^{'}$ decays to $K^{+} K^{-} π^{0}$ and $K^{+} K^{-} η$ . In these final states, the decay $ψ^{'} \to K_{2}^{*} (1430)^{+} K^{-} + c . c .$ is observed for the first time, and its branching fraction is measured to be $(7.12 \pm 0.62 (stat)_{- 0.61}^{+ 1.13} (syst)) \times 10^{- 5}$ , which indicates a violation of the helicity selection rule in $ψ^{'}$ decays. The branching fractions of $ψ^{'} \to K^{*} (892)^{+} K^{-} + c . c .$ , $ϕ η$ , and $ϕ π^{0}$ are also measured. The measurements are used to test the QCD predictions on charmonium decays.