"Table 169" of "Measurement of differential cross sections for the production of top quark pairs and of additional jets in lepton+jets events from pp collisions at $\sqrt{s} =$ 13 TeV"
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Differential and double-differential cross sections for the production of top quark pairs in proton-proton collisions at sqrt{s} = 13 TeV are measured as a function of kinematic variables of the top quarks and the top quark-antiquark (ttbar) system. In addition, kinematic variables and multiplicities of jets associated with the ttbar production are measured. This analysis is based on data collected by the CMS experiment at the LHC in 2016 corresponding to an integrated luminosity of 35.8/fb. The measurements are performed in the lepton+jets decay channels with a single muon or electron and jets in the final state. The differential cross sections are presented at the particle level, within a phase space close to the experimental acceptance, and at the parton level in the full phase space. The results are compared to several standard model predictions that use different methods and approximations. The kinematic variables of the top quarks and the ttbar system are reasonably described in general, though none predict all the measured distributions. In particular, the transverse momentum distribution of the top quarks is more steeply falling than predicted. The kinematic distributions and multiplicities of jets are adequately modeled by certain combinations of next-to-leading-order calculations and parton shower models.
在质心系能量√s=13 TeV的质子-质子碰撞中,我们按照顶夸克以及顶夸克-反顶夸克(ttbar)系统的运动学变量,测量了顶夸克对产生过程的微分与双微分截面。此外,我们还测量了与ttbar产生过程相关的喷注运动学变量及多重数。本分析基于大型强子对撞机(Large Hadron Collider, LHC)上的CMS实验(Compact Muon Solenoid)在2016年采集的、积分亮度为35.8 fb⁻¹的数据。本次测量针对末态包含单μ子或单电子以及喷注的轻子+喷注衰变道展开。我们在接近实验接受度的相空间内的粒子层次,以及全相空间内的部分子层次,给出了微分截面的结果。将上述测量结果与若干采用不同方法与近似方案的标准模型(Standard Model)预言进行了对比。总体而言,顶夸克与ttbar系统的运动学变量得到了合理的描述,但没有任何一个预言模型能够复现所有的测量分布。具体而言,顶夸克的横向动量分布的下降幅度比预言结果更为陡峭。部分次领头阶计算与部分子喷注模型的特定组合,能够较好地描述喷注的运动学分布与多重数。



