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

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. The product branching fraction is determined to be B(J/ψ\to γX) B(X\toωϕ) = (2.61 +- 0.27 (stat) +- 0.65$ (syst)) X 10^{-4}.