Observation of the decays $\ddot{I}{‡}_{cJ}\to \ddot{I}•\ddot{I}•\hat{I}\cdot$

Abstract

Using a data sample of $(448.1\pm 2.9)\times 10^6$ $\ddot{I}ˆ(3686)$ decays collected by the BESIII detector at the Beijing Electron Positron Collider (BEPCII), we observe the decays $\ddot{I}{‡}_{cJ}\to \ddot{I}•\ddot{I}•\hat{I}\cdot (J=0,1,2)$, where the $\ddot{I}{‡}_{cJ}$ are produced via the radiative processes $\ddot{I}ˆ(3686)\to {\hat{I}}^3\ddot{I}{‡}_{cJ}$. The branching fractions are measured to be $\mathcal{B}(\ddot{I}{‡}_{c0}\to \ddot{I}•\ddot{I}•\hat{I}\cdot )=(8.41\pm 0.74\pm 0.62)\times 10^{-4}$, $\mathcal{B}(\ddot{I}{‡}_{c1}\to \ddot{I}•\ddot{I}•\hat{I}\cdot )=(2.96\pm 0.43\pm 0.22)\times 10^{-4}$, and $\mathcal{B}(\ddot{I}{‡}_{c2}\to \ddot{I}•\ddot{I}•\hat{I}\cdot )=(5.33\pm 0.52\pm 0.39)\times 10^{-4}$, where the first uncertainties are statistical and the second are systematic. We also search for intermediate states in the $\ddot{I}•\ddot{I}•$ or $\hat{I}\cdot \ddot{I}•$ combinations, but no significant structure is seen due to the limited statistics.

10 pages,5 figures,