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arXiv · 0710.3091

First observation of J/ψand ψ(2S) decaying to n K^0_S\barΛ+c.c

BES Collaboration
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Abstract

The decays of $\jpsi$ and $\psip$ to ${n}{K^0_S}\barΛ+c.c.$ are observed and measured for the first time, and the perturbative QCD ``12%'' rule is tested, based on $5.8 \times 10^7$ $\jpsi$ and $1.4 \times 10^7$ $\psip$ events collected with BESII detector at the Beijing Electron-Positron Collider. No obvious enhancement near $n\barΛ$ threshold in $\jpsi \to {n}{K^0_S}\barΛ+c.c.$ is observed, and the upper limit on the branching ratio of $\jpsi \to {K^0_S} X, X \to n \bar Λ$ is determined.

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BES Collaboration. 2007-12-03. First observation of J/ψand ψ(2S) decaying to n K^0_S\barΛ+c.c. https://doi.org/10.1016/j.physletb.2007.11.087

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