Reactionπ−p→ϕϕnand Evidence for Glueballs

The authors have detected 1203 events of the reaction ${\ensuremath{\pi}}^{\ensuremath{-}}p\ensuremath{\rightarrow}\ensuremath{\phi}\ensuremath{\phi}n$ at 22 GeV/c, and have performed a partial-wave analysis of the $\ensuremath{\phi}\ensuremath{\phi}$ system. The results are well represented by two resonances, both with quantum numbers ${I}^{G}={0}^{+}$, ${J}^{\mathrm{PC}}={2}^{++}$. The breakdown of the Okubo-Zweig-Iizuka suppression observed in this reaction is naturally explained in the context of QCD if these states are considered to be glueball candidates.