Measurement of the branching fractions of $\ddot{I}{‡}_{cJ}\to \ddot{I}{€}^{+}\ddot{I}{€}^{-}\ddot{I}{€}^0\ddot{I}{€}^0$ via $\ddot{I}ˆ(3686)\to {\hat{I}}^3\ddot{I}{‡}_{cJ}$

Abstract

Using $(2712.4\pm 14.3)\times 10^6$ $\ddot{I}ˆ(3686)$ events collected with the BESIII detector operating at BEPCII, the branching fractions of $\ddot{I}{‡}_{cJ}\to \ddot{I}{€}^{+}\ddot{I}{€}^{-}\ddot{I}{€}^0\ddot{I}{€}^0$ ($J=0,1,2$) are measured via the radiative transition $\ddot{I}ˆ(3686)\to {\hat{I}}^3\ddot{I}{‡}_{cJ}$. The results are $\mathcal{B}(\ddot{I}{‡}_{c0}\to \ddot{I}{€}^{+}\ddot{I}{€}^{-}\ddot{I}{€}^0\ddot{I}{€}^0)=(3.10\pm 0.01\pm 0.14)\times 10^{-2}$, $\mathcal{B}(\ddot{I}{‡}_{c1}\to \ddot{I}{€}^{+}\ddot{I}{€}^{-}\ddot{I}{€}^0\ddot{I}{€}^0)=(1.16\pm 0.01\pm 0.05)\times 10^{-2}$, and $\mathcal{B}(\ddot{I}{‡}_{c2}\to \ddot{I}{€}^{+}\ddot{I}{€}^{-}\ddot{I}{€}^0\ddot{I}{€}^0)=(1.92\pm 0.01\pm 0.08)\times 10^{-2}$, where the first uncertainties are statistical and the second systematic. The dominant intermediate states are found to be $\ddot{I}{‡}_{cJ}\to \ddot{I}{}^{+}\ddot{I}{}^{-}$. These results supersede the previous most precise measurements and provide significantly improved precision.