Abstract：
A test of lepton flavor universality inB±→K±μ+μ-andB±→K±e+e-decays, as well as a measurement of differential and integrated branching fractions of a nonresonantB±→K±μ+μ-decay are presented. The analysis is made possible by a dedicated data set of proton-proton collisions ats=13TeVrecorded in 2018, by the CMS experiment at the LHC, using a special high-rate data stream designed for collecting about 10 billion unbiased b hadron decays. The ratio of the branching fractionsB(B±→K±μ+μ-)toB(B±→K±e+e-)is determined from the measured double ratioR(K)of these decays to the respective branching fractions of theB±→J/ψK±withJ/ψ→μ+μ-ande+e-decays, which allow for significant cancellation of systematic uncertainties. The ratioR(K)is measured in the range1.1
摘要：
在B±→K±μμ-和B±→K±e-衰减中测试轻子风味的普遍性，以及非共振B±→K±μμ衰减的微分和积分分支分数的测量。通过LHC的CMS实验，在2018年记录的质子-质子碰撞ats=13TeV的专用数据集使分析成为可能，使用特殊的高速率数据流，旨在收集约100亿个无偏b强子衰变。分支分数B（B±→K±μ-）与B（B±→K±e-）的比率是根据测得的这些衰变的双比率R（K）与B的相应分支分数确定的。这可以显著消除系统的不确定性。比率R(K)在1.1
