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arXiv · 0810.1896

First measurements of J/Psi decays into $\Sigma^+ \bar{\Sigma}^-$ and $\Xi^0 \bar{\Xi}^0$

BES Collaboration
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Abstract

Based on 58 million J/Psi events collected with the BESII detector at the BEPC, the baryon pair processes J/Psi to $\Sigma^+ \bar{\Sigma}^-$ and J/Psi to $\Xi^0 \bar{\Xi}^0$ are observed for the first time. The branching fractions are measured to be ${\cal B}(J/Psi to \Sigma^+ \bar{\Sigma}^-)=(1.50\pm 0.10\pm 0.22)\times 10^{-3}$ and ${\cal B}(J/Psi to \Xi^0 \bar{\Xi}^0)=(1.20\pm 0.12\pm 0.21)\times 10^{-3}$, where the first errors are statistical and the second ones are systematic.

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BES Collaboration. 2008-10-10. First measurements of J/Psi decays into $\Sigma^+ \bar{\Sigma}^-$ and $\Xi^0 \bar{\Xi}^0$. https://doi.org/10.1103/physrevd.78.092005

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