Evidence of doubly OZI-suppressed decay $\hat{I}{\cdot }_c\to \ddot{I}‰\ddot{I}•$ in the radiative decay $J/\ddot{I}ˆ\to {\hat{I}}^3\hat{I}{\cdot }_c$

Abstract

Using a sample of $(10087\pm 44)\times 10^6$ $J/\ddot{I}ˆ$ events collected with the BESIII detector at the BEPCII collider, the first evidence for the doubly OZI-suppressed decay $\hat{I}{\cdot }_c\to \ddot{I}‰\ddot{I}•$ is reported with a significance of 4.0$\ddot{I}ƒ$. The branching fraction of $\hat{I}{\cdot }_c\to \ddot{I}‰\ddot{I}•$ is measured to be $\mathcal{B}(\hat{I}{\cdot }_c\to \ddot{I}‰\ddot{I}•)=(3.86\pm 0.92\pm 0.62)\times 10^{-5}$, where the first uncertainty is statistical and the second is systematic. This result provides valuable insights into the underlying mechanisms of charmonium decays, particularly for processes such as $\hat{I}{\cdot }_c\to VV$ (where $V$ represents a vector meson).