"Table 6" 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"
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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.
本数据集针对质心系能量$sqrt{s}=13$ TeV的质子-质子碰撞过程,测量了高度洛伦兹增强的成对产生顶夸克的微分截面,分析变量涵盖顶夸克与顶夸克-反顶夸克($tar{t}$)系统的运动学可观测量。 所用数据取自欧洲核子研究中心(CERN)大型强子对撞机(Large Hadron Collider, LHC)上的ATLAS探测器在2015年与2016年采集的、积分亮度为$36.1 ext{fb}^{-1}$的实验数据。 本分析选取末态包含两个大半径喷注的事件:其中一个喷注的横向动量$p_{ m T} > 500 ext{GeV}$,另一个喷注的横向动量$p_{ m T} > 350 ext{GeV}$。 通过喷注子结构信息以及与$b$标记喷注($b$-tagged jet)的关联,将顶夸克候选事件与多喷注本底区分开来。 测量得到的能谱针对探测器效应进行修正,最终校准至粒子级 fiducial 相空间(fiducial phase space)与部分子级受限相空间,并通过计算$chi^2$值与多款蒙特卡洛(Monte Carlo)模拟结果开展对比。 fiducial相空间区域内的$tar{t}$产生截面测量值为$292 pm 7 ext{(stat)} pm 76 ext{(syst)}$ fb,可与理论预言值$384 pm 36$ fb进行对比。



