标题： 窄Upsilon共振态的缪子分支比的测量在CLEO 显示英文标题

标题： Measurment of the Muonic Branching Fraction of the Narrow Upsilon Resonances at CLEO

摘要： 三个窄的Upsilon共振态衰变为mu+mu-的分支比通过分析CLEO III探测器在共振态附近收集的约4.3 1/fb e+e-数据进行了测量。 分支比B(Y(1S)到mu+mu-) = (2.49 +- 0.02 +- 0.07)% 与当前世界平均值一致，但B(Y(2S)到mu+mu-) = (2.03 +- 0.03 +- 0.08)% 和 B(Y(3S)到mu+mu-) = (2.39 +- 0.07 +- 0.10)% 明显大于以前的结果。 这些新的缪子分支比意味着Y(2S)和Y(3S)共振态的总衰变宽度更窄，并且依赖于这些衰变确定的其他分支比更低。 显示英文摘要

摘要： The decay branching fractions of the three narrow Upsilon resonances to mu+mu- have been measured by analyzing about 4.3 1/fb e+e- data collected in the vicinity of the resonances with the CLEO III detector. The branching fraction B(Y(1S) to mu+mu-) = (2.49 +- 0.02 \+- 0.07)% is consistent with the current world average but B(Y(2S) to mu+mu-) = (2.03 +- 0.03 +- 0.08)% and B(Y(3S) to mu+mu-) = (2.39 +- 0.07 +- 0.10)% are significantly larger than prior results. These new muonic branching fractions imply a narrower total decay width for the Y(2S) and Y(3S) resonances and lower other branching fractions that rely on these decays in their determination.