Observation of a near-threshold enhancement in the ωϕmass spectrum from the doubly OZI suppressed decay J/ψ\to γωϕ

Abstract

An enhancement near threshold is observed in the ωϕinvariant mass spectrum from the doubly OZI suppressed decays of J/ψ\to γωϕ, based on a sample of 5.8 X 10^7 J/ψevents collected with the BESII detector. A partial wave analysis shows that this enhancement favors J^P = 0^+, and its mass and width are M = 1812^{+19}_{-26} (stat) +- 18 (syst) MeV/c^2 and Γ= 105+-20 (stat) +- 28$(syst)MeV/c^2.TheproductbranchingfractionisdeterminedtobeB(J/\ddot{I}ˆ\to {\hat{I}}^{3}X)B(X\to \ddot{I}‰\ddot{I}•)=(2.61+-0.27(stat)+-0.65$ (syst)) X 10^{-4}.

Accepted by PRL, the version to be appeared in PRL