论文标题
$ \ text {t} \ bar {\ text {t}} $生产的横截面的测量，并在$ \ sqrt {s} = $ 13 tev
Measurement of the cross section for $\text{t}\bar{\text{t}}$ production with additional jets and b jets in pp collisions at $\sqrt{s} =$ 13 TeV
论文作者
论文摘要
横截面生产顶部夸克对的测量结果与底部夸克（$σ_\ Mathrm {t \ bar {t} b \ bar {b {b}} $）的测量结果，以及与任何风味或gluons或gluons的夸克（$σ_\ mathrm and thersrm and the prestriore）的Quarks and the $ the $ pry ate $ a {该数据是在2016年在LHC的CMS实验的质子质子碰撞中收集的，在质子质量碰撞中，对应于35.9 fb $^{ - 1} $的综合发光度。测量值在基准相空间中进行，并将其外推到整个相空间，分别在Dilepton和Lepton+Jets通道中进行，其中Lepton对应于电子或MUON。 DILEPTON和LEPTON+JETS频道的结果分别为$σ_\ Mathrm {t \ bar {t} 0.001（STAT）$ \ pm $ 0.001（SYST）和0.020 $ \ pm $ 0.001（STAT）$ \ pm $ 0.001（SYST）。 $σ_\ Mathrm {t \ bar {t} b \ bar {b}} $的值是从$σ_\ mathrm {t \ bar {t} jjj} $和横截面比率和分别获得的横截面比率的。 0.03（STAT）$ \ pm $ 0.07（SYST）PB。这些测量值是迄今为止最精确的，并且在不确定性内是一致的，并且在量子染色体动力学中使用矩阵元素计算的标准模型期望与矩阵淋浴相匹配。
Measurements of the cross section for the production of top quark pairs in association with a pair of jets from bottom quarks ($σ_\mathrm{t\bar{t}b\bar{b}}$) and in association with a pair of jets from quarks of any flavor or gluons ($σ_\mathrm{t\bar{t}jj}$) and their ratio are presented. The data were collected in proton-proton collisions at a center-of-mass energy of 13 TeV by the CMS experiment at the LHC in 2016 and correspond to an integrated luminosity of 35.9 fb$^{-1}$. The measurements are performed in a fiducial phase space and extrapolated to the full phase space, separately in the dilepton and lepton+jets channels, where lepton corresponds to either an electron or a muon. The results for the dilepton and lepton+jets channels, respectively, are $σ_\mathrm{t\bar{t}jj}$ = 2.36 $\pm$ 0.02 (stat) $\pm$ 0.20 (syst) pb and 31.0 $\pm$ 0.2 (stat) $\pm$ 2.9 (syst) pb, and for the cross section ratio 0.017 $\pm$ 0.001 (stat) $\pm$ 0.001 (syst) and 0.020 $\pm$ 0.001 (stat) $\pm$ 0.001 (syst). The values of $σ_\mathrm{t\bar{t}b\bar{b}}$ are determined from the product of the $σ_\mathrm{t\bar{t}jj}$ and the cross section ratio, obtaining, respectively, 0.040 $\pm$ 0.002 (stat) $\pm$ 0.005 (syst) pb and 0.62 $\pm$ 0.03 (stat) $\pm$ 0.07 (syst) pb. These measurements are the most precise to date and are consistent, within the uncertainties, with the standard model expectations obtained using a matrix element calculation at next-to-leading order in quantum chromodynamics matched to a parton shower.
