BES关于ψ(3770)和D介子产生与衰变的最新结果
摘要
利用BEPC上BES-II探测器在3.773 GeV收集的17.7 pb⁻¹数据样本，测量了3.773 GeV处D⁰D̄⁰和D+D-产生的截面。从约33 pb⁻¹在3.773 GeV附近获取的数据样本中，观察到3个D+→μ+ν的纯轻子衰变事件。测得分支比和衰变常数为BF(D+→μ+ν) = (0.120⁺⁰·⁰⁹²⁺⁰·⁰¹⁰₋₀.₀₆₃₋₀.₀₀₉)%和f_D = (365⁺¹²¹⁺³²₋₁₁₃₋₂₈) MeV。D⁰→K⁻e⁺ν、D⁰→π⁻e⁺ν和D+→K̄⁰e⁺ν的半轻子衰变分支比测得为BF(D⁰→K⁻e⁺ν_e) = (3.52 ± 0.36 ± 0.25)%，BF(D⁰→π⁻e⁺ν_e) = (0.36 ± 0.14 ± 0.03)%和BF(D+→K̄⁰e⁺ν_e) = (8.64 ± 1.51 ± 0.72)%。矢量形状因子确定为|f⁺_K(0)| = 0.75 ± 0.04 ± 0.03和|f⁺_π(0)| = 0.76 ± 0.15 ± 0.06。两个形状因子的比值提取为|f⁺_π(0)/f⁺_K(0)| = 1.01 ± 0.20 ± 0.08。衰变宽度之比测得为Γ(D⁰→K⁻e⁺ν)/Γ(D+→K̄⁰e⁺ν) = 1.04 ± 0.21 ± 0.08。从约27 pb⁻¹的数据样本中，观察到ψ(3770)→J/ψ π+π-非DD̄衰变的证据。分支比确定为BF(ψ(3770)→J/ψ π+π-) = (0.34 ± 0.14 ± 0.08)%，对应于部分宽度Γ(ψ(3770)→J/ψ π+π-) = (80 ± 32 ± 21) keV。
引用
@article{arxiv.hep-ex/0406027,
title = {Recent Bes Results on psi(3770) and D Meson Production and Decay},
author = {G. Rong},
journal= {arXiv preprint arXiv:hep-ex/0406027},
year = {2007}
}
备注
6 pages, 7 figures, To appear in the proceedings of 39th Recontres de Moriond on Electroweak Interactions and Unified Theories, LaThuile, Aosta Valley, Italy, 21-28 March, 2004