Measurement of branching fractions for $\ddot{I}ˆ(3686)\to {\hat{I}}^3\hat{I}{\cdot }^{\prime },{\hat{I}}^3\hat{I}\cdot$ and ${\hat{I}}^3\ddot{I}{€}^0$

Abstract

Using a data sample of $448\times 10^6$ $\ddot{I}ˆ(3686)$ events collected with the BESIII detector operating at the BEPCII storage ring, the decays $\ddot{I}ˆ(3686)\to {\hat{I}}^3\hat{I}\cdot$ and $\ddot{I}ˆ(3686)\to {\hat{I}}^3\ddot{I}{€}^0$ are observed with a statistical significance of $7.3\ddot{I}ƒ$ and $6.7\ddot{I}ƒ$, respectively. The branching fractions are measured to be $\mathcal{B}(\ddot{I}ˆ(3686)\to {\hat{I}}^3\hat{I}\cdot )=(0.85\pm 0.18\pm 0.05)\times 10^{-6}$ and $\mathcal{B}(\ddot{I}ˆ(3686)\to {\hat{I}}^3\ddot{I}{€}^0)=(0.95\pm 0.16\pm 0.05)\times 10^{-6}$. In addition, we measure the branching fraction of $\ddot{I}ˆ(3686)\to {\hat{I}}^3\hat{I}{\cdot }^{\prime }$ to be $\mathcal{B}(\ddot{I}ˆ(3686)\to {\hat{I}}^3\hat{I}{\cdot }^{\prime })=(125.1\pm 2.2\pm 6.2)\times 10^{-6}$, with improved precision compared to previous results.