Observation of $K^{\ast }(892{)}^0{\bar{K}}^{\ast }(892{)}^0$ in $\ddot{I}{‡}_{cJ}$ Decays

Abstract

$K^{\ast }(892{)}^0{\bar{K}}^{\ast }(892{)}^0$ signals from $\ddot{I}{‡}_{cJ}(J=0,1,2)$ decays are observed for the first time using a data sample of 14 million $\ddot{I}ˆ(2S)$ events accumulated at the BES II detector. The branching fractions $\mathcal{B}(\ddot{I}{‡}_{cJ}\to K^{\ast }(892{)}^0{\bar{K}}^{\ast }(892{)}^0)$ $(J=0,1,2)$ are determined to be $(1.55\pm 0.35\pm 0.30)\times 10^{-3}$, $(1.58\pm 0.32\pm 0.29)\times 10^{-3}$, and $(4.67\pm 0.55\pm 0.85)\times 10^{-3}$ for the $\ddot{I}{‡}_{c0}$, $\ddot{I}{‡}_{c1}$ and $\ddot{I}{‡}_{c2}$ decays, respectively, where the first errors are statistical and the second are systematic. The significances of these signals are about 4.2$\ddot{I}ƒ$, 4.3$\ddot{I}ƒ$, and 7.5$\ddot{I}ƒ$, respectively.

8 pages, 6 figures