标量轻子夸克和稀有衰变Λ_b→Λl^+~l-（英文）

Scalar Leptoquarks and the Rare Decays Λ_b→Λl^+l^-

考虑到电弱精确测量数据对标量轻子夸克(SLQ)自由参数的限制,研究此类新粒子对稀有衰变Λ_b→Λl^+l^-(l=e,μ和τ)的量子修正.我们的计算结果表明:由于当前实验数据对参数|λ^(31λ)^(21)*|/M_(LQ)~2的限制是非常小,SLQ对Λ_b→Λe^+e^-衰变过程的贡献很大.如果在不久的将来,分支比Br(Λ_b→Λμ^+μ^-)在LHCb上可以得到更精确的测量,那么SLQ的间接信号就可能通过此衰变在LHCb上观测到.

Considering the constraints on the scalar leptoqaark （SLQ） free parameters from low energy precision measurement data,the correction effects of the SLQs on the rare decays Ab→Al^＋ l^- with l = e,μ and τ were investigated. It was found that, for the decay Ab→Ae ^＋e^-, since the constraints given by the current experimental data on the combination coupling I A31A21. I/M20 is very loose,the contributions of the SLQs to Ab→Ae^ ＋e^- are too large. If the branching ratio Br （Ab→Aμ ＋μ- ） can be precisely measured at the LHCb in near future, the indirect signals of the SLQs might be observed at the LHCb.