Observation of $\ddot{I}{‡}_{cJ}\to 4K_S^0$

Abstract

By analyzing $(448.1\pm 2.9)\times 10^6$ $\ddot{I}ˆ(3686)$ events collected with the BESIII detector operating at the BEPCII collider, the decays of $\ddot{I}{‡}_{cJ}\to 4K_S^0$ ($J=0,1,2$) are observed for the first time with statistical significances of 26.5$\ddot{I}ƒ$, 5.9$\ddot{I}ƒ$ and 11.4$\ddot{I}ƒ$, respectively. The product branching fractions of $\ddot{I}ˆ(3686)\to {\hat{I}}^3\ddot{I}{‡}_{cJ}$, $\ddot{I}{‡}_{cJ}\to 4K_S^0$ are presented and the branching fractions of $\ddot{I}{‡}_{cJ}\to 4K_S^0$ decays are determined to be ${\mathcal{B}}_{\ddot{I}{‡}_{c0}\to 4K_S^0}$=$(5.76\pm 0.34\pm 0.38)$$\times 10^{-4}$, ${\mathcal{B}}_{\ddot{I}{‡}_{c1}\to 4K_S^0}$=$(0.35\pm 0.09\pm 0.03)$$\times 10^{-4}$ and ${\mathcal{B}}_{\ddot{I}{‡}_{c2}\to 4K_S^0}$=$(1.14\pm 0.15\pm 0.08)$$\times 10^{-4}$, where the first uncertainties are statistical and the second are systematic, respectively.