"Table 68" of "Properties of jet fragmentation using charged particles measured with the ATLAS detector in $pp$ collisions at $\sqrt{s}=13$ TeV"

CERN-LHC. This paper presents a measurement of quantities related to the formation of jets from high energy quarks and gluons (fragmentation). Jets with $100$ GeV $ 500$ MeV~and $|\eta| < 2.5$~are used to probe the detailed structure of the jet. The fragmentation properties of the more forward and the more central of the leading two jets from each event are studied. The data are unfolded to correct for detector resolution and acceptance effects. Comparisons to parton shower Monte Carlo generators indicate that existing models provide a reasonable description of the data across a wide range of phase space, but there are also significant differences. Furthermore, the data are interpreted in the context of quark- and gluon-initiated jets by exploiting the rapidity dependence of the jet flavor fraction. A first measurement of the charged-particle multiplicity using model-independent jet labels (topic modeling) provides a promising alternative to traditional quark- and gluon- extractions using simulation input. The simulations provide a reasonable description of the quark-like data across the jet $p_\text{T}$ range presented in this measurement, but the gluon-like data have systematically fewer charged particles than the simulations. Uncertainties are broken down by category and should be treated as fully correlated between bins and between observables except for statistical uncertainties.

欧洲核子研究中心大型强子对撞机（CERN-LHC）。本研究报道了高能夸克与胶子喷注碎裂过程相关物理量的测量结果。选取横向动量（$p_ ext{T}$）介于100 GeV至500 GeV、赝快度$|eta| < 2.5$的喷注，用于探究喷注的精细结构。针对每个事件中的两束领头喷注，本研究分别对其中更具前向性与更中心的喷注的碎裂特性展开分析。为校正探测器分辨与接收度效应，对实验数据进行了解褶处理。与部分子喷注蒙特卡洛（parton shower Monte Carlo）发生器的对比结果显示，现有模型可在较宽相空间范围内合理描述实验数据，但二者仍存在显著差异。此外，本研究利用喷注味组分的快度依赖性，将实验数据按夸克起源与胶子起源喷注进行归类阐释。本工作首次采用与模型无关的喷注标签结合主题建模（topic modeling）方法测量带电粒子多重数，为替代传统基于模拟输入的夸克与胶子喷注甄别方法提供了极具前景的新思路。模拟结果可在本次测量涵盖的喷注横向动量区间内较好描述类夸克喷注数据，但类胶子喷注的带电粒子多重数系统性低于模拟结果。本工作的不确定度按类别划分，除统计不确定度外，各分箱与各观测量间的不确定度均视为完全相关。