Results are reported based on samples of 58 million $\jpsi$ and 14 million $\psip$ decays obtained by the BESII experiment. Improved branching fraction measurements are determined, including branching fractions for $\jpsi\to\ppp$, $\psip\ra \pi^0\J$, $\eta\J$, $\pi^0 \pi^0 J/\psi$, anything $J/\psi$, and $\psi(2S)\ar\gamma\chi_{c1},\gamma\chi_{c2}\ar\gamma\gamma\jpsi$. The decay $J/\psi \to \omega \pi ^+\pi ^-$ is studied. At low $\pi \pi$ mass, a large, broad peak due to the $\sigma$ is observed, and its pole position is determined. Results are presented on $\psi(2S)$ and $J/\psi$ hadronic decays to $K^0_SpK^-\bar n$ and $K^0_S\bar p K^+n$ final states. No significant $\Theta(1540)$ signal, the pentaquark candidate, is observed, and upper limits are set. An enhancement near the $m_p + M_{\Lambda}$ mass threshold is observed in the $p\bar{\Lambda}$ invariant mass spectrum from $J/\psi \to p K^- \bar{\Lambda} + c.c.$ decays. It can be fit with an S-wave Breit-Wigner resonance with a mass $m=2075\pm 12 (stat) \pm 5 (syst)$ MeV and a width of $\Gamma =90 \pm 35 (stat) \pm 9 (syst)$ MeV.
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机译：根据通过BESII实验获得的5800万美元/ psi和1400万美元/ psip衰减样本报告了结果。确定改进的分支分数测量，包括$ \ jpsi \ to \ ppp $，$ \ psip \ ra \ pi ^ 0 \ J $，$ \ eta \ J $，$ \ pi ^ 0 \ pi ^ 0 J的分支分数/ \ psi $，任何$ J / \ psi $和$ \ psi（2S）\ ar \ gamma \ chi_ {c1}，\ gamma \ chi_ {c2} \ ar \ gamma \ gamma \ jpsi $。研究了到$ω\ pi ^ + \ pi ^-$的衰减$ J / \ psi \。在低的质量下，观察到由于σ引起的大而宽的峰，并确定了其极点位置。结果以$ \ psi（2S）$和$ J / \ psi $强子衰变表示为$ K ^ 0_SpK ^-\ bar n $和$ K ^ 0_S \ bar p K ^ + n $最终状态。没有观察到明显的$ \ Theta（1540）$信号（五夸克候选物），并且没有设置上限。在$ p \ bar {\ Lambda} $不变质谱图中，从$ J / \ psi \到p K ^-\ bar {\ Lambda} +，在$ m_p + M _ {\ Lambda} $质量阈值附近观察到增强。 cc $衰减。它可以与质量为$ m = 2075 \ pm 12（stat）\ pm 5（syst）$ MeV且宽度为$ \ Gamma = 90 \ pm 35（stat）的S波Breit-Wigner谐振配合。 pm 9（syst）$ MeV。
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