"Table 72" of "Measurements of $t\bar{t}$ differential cross-sections of highly boosted top quarks decaying to all-hadronic final states in $pp$ collisions at $\sqrt{s}=13\,$ TeV using the ATLAS detector"

Measurements are made of differential cross-sections of highly boosted pair-produced top quarks as a function of top-quark and $t\bar{t}$ system kinematic observables using proton--proton collisions at a center-of-mass energy of $\sqrt{s} = 13$ TeV. The data set corresponds to an integrated luminosity of $36.1$ fb$^{-1}$, recorded in 2015 and 2016 with the ATLAS detector at the CERN Large Hadron Collider. Events with two large-radius jets in the final state, one with transverse momentum $p_{\rm T} > 500$ GeV and a second with $p_{\rm T} > 350$ GeV, are used for the measurement. The top-quark candidates are separated from the multijet background using jet substructure information and association with a $b$-tagged jet. The measured spectra are corrected for detector effects to a particle-level fiducial phase space and a parton-level limited phase space, and are compared to several Monte Carlo simulations by means of calculated $\chi^2$ values. The cross-section for $t\bar{t}$ production in the fiducial phase-space region is $292 \pm 7 \rm{(stat)} \pm 76 \rm{(syst)}$ fb, to be compared to the theoretical prediction of $384 \pm 36$ fb.

本研究利用欧洲核子研究中心（CERN）大型强子对撞机（Large Hadron Collider, LHC）上的ATLAS探测器（ATLAS detector）采集的质子-质子碰撞（proton-proton collisions）数据开展分析，质心系能量（center-of-mass energy）为$sqrt{s}=13$ TeV，测量了高动量增强的成对产生顶夸克（top quark）的微分截面（differential cross-sections），该测量以顶夸克与顶反顶夸克对（$tar{t}$）系统的运动学可观测量作为函数变量。本次分析使用的数据采集于2015至2016年，对应的积分亮度（integrated luminosity）为$36.1 mathrm{fb}^{-1}$。本次测量选取末态包含两个大半径喷注（large-radius jets）的事件：其中一个喷注的横向动量（transverse momentum, $p_{
m T}$）大于500 GeV，另一个喷注的$p_{
m T}$大于350 GeV。研究通过喷注子结构（jet substructure）信息以及与b标记喷注（$b$-tagged jet）的关联，从多喷注本底（multijet background）中甄别出顶夸克候选事例。将测量得到的能谱修正至扣除探测器效应后的粒子级 fiducial相空间（fiducial phase space）与部分子级受限相空间（parton-level limited phase space），并通过计算卡方（$chi^2$）值与多款蒙特卡洛模拟（Monte Carlo simulations）结果进行比对。在该fiducial相空间区域内，顶反顶夸克对产生截面的测量结果为$292 pm 7 mathrm{(stat)} pm 76 mathrm{(syst)}$ fb，其中$mathrm{(stat)}$为统计误差（statistical uncertainty）、$mathrm{(syst)}$为系统误差（systematic uncertainty），该结果与理论预言值$384 pm 36$ fb可供交叉验证。