TheCP-violating weak phase?sand the decay width differenceΔΓsbetween the light and heavyBs0mass eigenstates are measured with the CMS detector at the LHC in a sample of48500reconstructedBs0→J/ψ?(1020)→μ+μ?K+K?events. The measurement is based on a data sample corresponding to an integrated luminosity of96.4fb?1, collected in proton-proton collisions ats=13TeVin 2017–2018. To extract the values of?sandΔΓs, a time-dependent and flavor-tagged angular analysis of theμ+μ?K+K?final state is performed. The analysis employs a dedicated tagging trigger and a novel opposite-side muon flavor tagger based on machine learning techniques. The measurement yields?s=?11±50(stat)±10(syst)mradandΔΓs=0.114±0.014(stat)±0.007(syst)ps?1, in agreement with the standard model predictions. When combined with the previous CMS measurement ats=8TeV, the following values are obtained:?s=?21±44(stat)±10(syst)mrad,ΔΓs=0.1032±0.0095(stat)±0.0048(syst)ps?1, a significant improvement over the 8?TeV result.
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机译：违反弱相位？砂衰减宽度差异Δγ在48500ReConstructedBS0→j /ψ→μ+μ≤kk k k k？事件中，用LHC的CMS检测器用CMS检测器测量光线和重型偏见。（1020）→μ≤k+？事件。测量基于对应于96.4FBα1的集成光度的数据样本，在质子 - 质子碰撞中收集在= 13tevin 2017-2018中。为了提取λΔγs的值，执行μ+μΔk+ k的时间依赖性和风味标记的角度分析。该分析采用专用标记触发器和基于机器学习技术的新型相对侧μ子风味标记器。测量产率ΔS=α11±50（STAT）±10（STYS）MradandΔγs= 0.114±0.014（STAT）±0.007（SYST）PS？1，与标准模型预测一致。当与先前的CMS测量ATS = 8TEV结合时，获得以下值：ΔS=α24（STAT）±10（STYST）MRAD，Δγs= 0.1032±0.0095（STAT）±0.0048（SYST）PS？1 ，8？TEV结果的显着改善。
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