【摘 要】
：
利用工作在北京正负电子对撞机(BEPC)上的北京谱仪(BES)收集到的33pb-1的ψ(3770)数据,寻找D介子味道改变中性流(FCNC)和轻子数不守恒(LNV)的稀有衰变,包括4个D0介子的衰变模
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利用工作在北京正负电子对撞机(BEPC)上的北京谱仪(BES)收集到的33pb-1的ψ(3770)数据,寻找D介子味道改变中性流(FCNC)和轻子数不守恒(LNV)的稀有衰变,包括4个D0介子的衰变模式(-K0e+e-,φe+e-,ρ0e+e-和-K*0e+e-)和6个D+介子的衰变模式(K-e+e+,K+e+e-,π-e+e+,π+e+e-,K*-e+e+和K*-e+e-).没有发现信号,给出90%置信水平的上限.其中,D+介子的两个衰变模式D+→K*-e+e+和D+→K*+e+e-的上限是首次测量.
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