Search for $\ddot{I}{‡}_{c1}\to \ddot{I}{€}^{+}\ddot{I}{€}^{-}\hat{I}{\cdot }_c$ via $\ddot{I}ˆ(3686)\to {\hat{I}}^3\ddot{I}{‡}_{c1}$

Abstract

Utilizing $(2712.4\pm 14.3)\times 10^6$ $\ddot{I}ˆ(3686)$ events collected with the BESIII detector at the BEPCII collider, we search for the hadronic transition process $\ddot{I}{‡}_{c1}\to \ddot{I}{€}^{+}\ddot{I}{€}^{-}\hat{I}{\cdot }_c$ following the decay $\ddot{I}ˆ(3686)\to {\hat{I}}^3\ddot{I}{‡}_{c1}$. No significant signal is observed, and an upper limit of $\mathcal{B}(\ddot{I}{‡}_{c1}\to \ddot{I}{€}^{+}\ddot{I}{€}^{-}\hat{I}{\cdot }_c)$ is determined to be $3.1times10^{-4}$~at 90\% confidence level, which is one order of magnitude more stringent than the previous measurement.