期刊论文

Bai, JZ

中文

中国物理C

1674-1137

2002

26

1

8-16

10.3321/j.issn:0254-3052.2002.01.005

国家自然科学基金 （ 1 9991 4 80 ）； 中国科学院重大及特别支持项目 （KJ95T -0 3）资助~~；

本校为其他机构

用BES I的7.8 * 10~6 J/ψ数据更为精确地测定了J/ψ→π~03(π~+π~-)和J/ψ→ω2(π~+π~-)的分支比(Br(J/ψ→π~03(π~+π~-)) = (2.52±0.06±0.43)%，Br(J/ψ→ω2(π~+π~-)) = (1.31±0.09±0.21)%。同时对4π不变质量谱和ωππ不变质量谱进行研究分析，试图观察是否存在有兴趣的信号。

The decay mode of J/psi-->pidegrees3(pi(+)pi(-)) was studied very little before. There axe no informations except branching ratios for this channel in PDG book which based on less than 0.2 x 10(6) J/psi events of MARK I. Now, BES I has a data sample of 7.8 x 10(6) J/psi events, we can make more accurate results than MARK I. Total of 3290 +/- 43 J/psi-->pidegrees3(pi(+)pi(-)) events including 1275 +/- 86 J/psi-->omega2(pi(+)pi(-)) events are selected. J/psi-->pidegrees3(pi(+)pi(-)) and J/psi-->omega2(pi(+)pi(-)) events have been generated with MC simulition for calculating events selection effi...