Experimental limit onι→γγand the interpretation of the iota as a glueball

By observing the reaction {γ}{γ}{→}Kₛ⁰{K}^{±{}}π^∓, the TPC/Two-Gamma experiment at the SLAC e⁺{e}^{{{-}}}$ storage ring PEP has obtained a 95%-confidence-level limit of ${{Γ}}_{{ι}{→}{γ}{γ}}$B({ι}{→}KK{}{π})1.6 keV for the {ι}(1450) meson. If, as is likely, the {ι} decays predominantly into KK{}{π}, the resulting Γ_ι→γγ limit appears to conflict with previous assignments of an observed {ρ}{γ} decay to {ι} and also with many analyses of {η}-{η}'-{ι} mixing. The contrast of this small {γ}{γ} width with the large rate for J/{ψ}{→}{γ}{ι} is evidence that the {ι} is a glueball with little admixture of qq{} states.