BES Results on Charmonium Decays and Transitions

Abstract

Results are reported based on samples of 58 million $J/\psi$ and 14 million $\psi(2S)$ decays obtained by the BESII experiment. Improved branching fraction measurements are determined, including branching fractions for $J/\psi\to\pi^+\pi^-\pi^0$, $\psi(2S)\to \pi^0 J/\psi$, $\eta J/\psi$, $\pi^0 \pi^0 J/\psi$, anything $J/\psi$, and $\psi(2S)\to\gamma\chi_{c1},\gamma\chi_{c2}\to\gamma\gamma\jpsi$. Using 14 million $\psi(2S)$ events, $f_0(980)f_0(980)$ production in $\chi_{c0}$ decays and $K^*(892)^0\bar K^*(892)^0$ production in $\chi_{cJ}~(J=0,1,2)$ decays are observed for the first time, and branching ratios are determined.