Evidence of psi(3770) non-DD-bar Decay to J/psi pi+pi-

BES Collaboration

Evidence of $\psi (3770)$ decays to a non-$D\bar{D}$ final state is observed. A total of $11.8\pm 4.8\pm 1.3$ $ψ(3770) \to \PPJP$ events are obtained from a data sample of 27.7 $\r…