Vector Gluonium as a Possible Explanation for AnomalousψDecays

Abstract

Recent experiments at SLAC show unexpectedly large values for the ratios (1) $\frac{B(\ensuremath{\psi}\ensuremath{\rightarrow}\ensuremath{\rho}\ensuremath{\pi})}{B({\ensuremath{\psi}}^{\ensuremath{'}}\ensuremath{\rightarrow}\ensuremath{\rho}\ensuremath{\pi})}$ and (2) $\frac{B(\ensuremath{\psi}\ensuremath{\rightarrow}{K}^{*}\overline{K})}{B({\ensuremath{\psi}}^{\ensuremath{'}}\ensuremath{\rightarrow}{K}^{*}\overline{K})}$. It is proposed that these anomalies are caused by the mixing of the ground-state isoscalar vector mesons ($\ensuremath{\omega}, \ensuremath{\phi}, \ensuremath{\psi}$) with a ${J}^{\mathrm{PC}}={1}^{\ensuremath{-}\ensuremath{-}}$ vector glueball ($O$) which was first postulated by Freund and Nambu in 1975. Its mass is estimated at \ensuremath{\simeq} 2.4 GeV and direct experimental searches for the $O$ are suggested.