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

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 نشر من قبل RongGang Ping
 تاريخ النشر 2007
  مجال البحث
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We investigate the decay and the production mechanism of the resonance X(1812) recently observed in the $jptogamma X(1812), X(1812)toomegaphi$ at BESII. The decay widths of $X(1812)toetaeta$,$ etaeta$,$ omegaphi$,$ K^+K^-$,$ rho^+rho^-$, $ omegaomega$,$ K^{*+}K^{*-}$ and $pi^+pi^-$ 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 $X(1812)toomegaphi$. It is also found that the decay widths for $X(1812)toetaeta$ and $etaeta$ 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 $Br(Xtoomegaphi)$ 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 $Gamma(jptogamma X)/Gamma(jptogamma K^{*+}K^{*-})=2.13^{+7.41}_{-1.85}$, which is close to the measured value $2.83pm0.92$.

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