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تسجيل مستخدم جديدSearch for $XYZ$ states in $Upsilon(1S)$ inclusive decays
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The branching fractions of the $Upsilon(1S)$ inclusive decays into final states with a $J/psi$ or a $psi(2S)$ are measured with improved precision to be $BR(Upsilon(1S)to J/psi + {rm anything})=(5.25pm 0.13(mathrm{stat.})pm 0.25(mathrm{syst.}))times 10^{-4}$ and $BR(Upsilon(1S)to psi(2S) + {rm anything})=(1.23pm 0.17(mathrm{stat.})pm 0.11(mathrm{syst.}))times 10^{-4}$. The first search for $Upsilon(1S)$ decays into $XYZ$ states that decay into a $J/psi$ or a $psi(2S)$ plus one or two charged tracks yields no significant signals for $XYZ$ states in any of the examined decay modes, and upper limits on their production rates in $Upsilon(1S)$ inclusive decays are determined.
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