Faculté des Sciences, Université Mohamed Premier and LPTPM, Oujda, Morocco.
CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille, France.
Phys Rev Lett. 2018 Oct 12;121(15):152002. doi: 10.1103/PhysRevLett.121.152002.
This Letter presents a normalized differential cross-section measurement in a fiducial phase-space region where interference effects between top-quark pair production and associated production of a single top quark with a W boson and a b-quark are significant. Events with exactly two leptons (ee, μμ, or eμ) and two b-tagged jets that satisfy a multiparticle invariant mass requirement are selected from 36.1 fb^{-1} of proton-proton collision data taken at sqrt[s]=13 TeV with the ATLAS detector at the LHC in 2015 and 2016. The results are compared with predictions from simulations using various strategies for the interference. The standard prescriptions for interference modeling are significantly different from each other but are within 2σ of the data. State-of-the-art predictions that naturally incorporate interference effects provide the best description of the data in the measured region of phase space most sensitive to these effects. These results provide an important constraint on interference models and will guide future model development and tuning.
这封信件介绍了在一个有显著顶夸克对产生和伴随产生单个顶夸克与 W 玻色子和 b 夸克的干涉效应的基准相空间区域中的归一化微分截面测量。该事件从 2015 年和 2016 年在 LHC 的 ATLAS 探测器上用质子-质子对撞数据采集的 36.1 fb^{-1}中，选取了具有精确两个轻子（ee、μμ 或 eμ）和两个 b 标记喷注的事件，这些喷注满足多粒子不变质量要求。结果与使用各种干涉处理策略的模拟预测进行了比较。干涉建模的标准方法彼此之间存在显著差异，但在数据的 2σ 范围内。自然包含干涉效应的最先进预测在对这些效应最敏感的测量相空间区域中，为数据提供了最佳描述。这些结果为干涉模型提供了重要的约束，并将指导未来的模型开发和调整。
