Study of X(1812) as a $(K^*\bar K^*)$ Molecular State

Abstract

We investigate the decay and the production mechanism of the resonance X(1812) recently observed in the $\jp\toγX(1812), X(1812)\toωϕ$ at BESII. The decay widths of $X(1812)\toηη'$,$ ηη$,$ ωϕ$,$ K^+K^-$,$ ρ^+ρ^-$, $ ωω$,$ K^{*+}K^{*-}$ and $π^+π^-$ are evaluated based on the scenario of the X(1812) as a candidate of $(\ksks)$ molecule. It turns out that the quark exchange mechanism plays an important role in the understanding of the large decay width for the $X(1812)\toωϕ$. It is also found that the decay widths for $X(1812)\toηη'$ and $ηη$ are enhanced by the quark exchange mechanism. These channels are suggested to be the tools to test the molecular scenario in experiment. The branching fraction of $Br(X\toωϕ)$ is evaluated to be about 4.60%. Searches for additional evidence about the X(1812) in $\jp$ radiative decays are reviewed. In the molecular scenario, the X(1812) production rate is also evaluated to be $Γ(\jp\toγX)/Γ(\jp\toγK^{*+}K^{*-})=2.13^{+7.41}_{-1.85}$, which is close to the measured value $2.83\pm0.92$.