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基于高亮度的重味物理实验产生大量y介子.在标准模型中详细地研究了以树图贡献为主的Y(nS)→Bc(lv)e(n=1,2,3)半轻衰变,给出了这些衰变过程的分支比,比值RY(nS),轻子自旋不对称和前后不对称.最终的数值结果表明,所有的Y(nS)→Bc(lv)e的半轻衰变均有较大的分支比,且量级为10-10～10-9.因此,这些过程均有望被LHC和SupperKEKB/Belle-Ⅱ实验所观测到.“,”Motivated by the abundant data samples Y at high-luminosity heavy-flavor experiments in the future,the treedominated and CKM-favored Y(nS) → Bce(lv)e(n =1,2,3) decays are studied within the Standard Model in this paper.The theoretical predictions for the observables including the branching fraction,the ratio RY(nS),the lepton spin asymmetry and the forward-backward asymmetry are presented.Numerically,the Y(nS) → Bc(lv)e decays have relative large branching fractions of the order O(10 10-10-9),and are hopeful to be observed by the running LHC and upgrading SuperKEKB/Belle-Ⅱ experiments in the future.