Measurement of J/ψ leptonic width with the KEDR detector

作     者：A.G.Shamov 

作者机构：Budker Institute of Nuclear Physics 

出 版 物：《Chinese Physics C》 (中国物理C（英文版）)

年 卷 期：2010年第34卷第6期

页      面：836-841页

核心收录：

学科分类：07[理学] 070202[理学-粒子物理与原子核物理] 0702[理学-物理学] 

基　　金：Supported by the Russian Foundation for Basic Research,Grants 08-02-00258,09-02-08537 RF Presidential Grant for Sc.Sch.NSh-5655.2008.2 

主　　题：J/ψ meson lepton width full width 

摘      要：We report a new precise determination of the leptonic widths of the J/psi meson performed with the KEDR detector at the VEPP-4M e^＋e^- collider. The measured values of the J/psi parameters are： Гee×Гee/P = 0.3323±0.0064 （stat.）±0.0048 （syst.） keV,Гee×Гμμ/Г = 0.3318±0.0052 （stat.） ±0.0063 （syst.） keY. Assuming eμ universality and using the table value of the branching ratios the leptonic Г11 = 5.59 ± 0.12 keV width and the total Г = 94.1±2.7 keV widths were obtained. We also discuss in detail a method to calculate radiative corrections at a narrow resonance.