Revisiting the top-quark pair production at future e^(+)e^(−)colliders  

作　　者：马进 王声权 孙婷 申建明 吴兴刚 Jin Ma;Sheng-Quan Wang;Ting Sun;Jian-Ming Shen;Xing-Gang Wu(Department of Physics,Guizhou Minzu University,Guiyang 550025,China;School of Physics and Electronics,Hunan Provincial Key Laboratory of High-Energy Scale Physics and Applications,Hunan University,Changsha 410082,China;Department of Physics,Chongqing Key Laboratory for Strongly Coupled Physics,Chongqing University,Chongqing 401331,China)

机构地区：[1]Department of Physics,Guizhou Minzu University,Guiyang 550025,China [2]School of Physics and Electronics,Hunan Provincial Key Laboratory of High-Energy Scale Physics and Applications,Hunan University,Changsha 410082,China [3]Department of Physics,Chongqing Key Laboratory for Strongly Coupled Physics,Chongqing University,Chongqing 401331,China

出　　处：《Chinese Physics C》2024年第4期82-88,共7页中国物理C（英文版）

基　　金：the Natural Science Foundation of China(12175025,12147102,12265011);by the Projects of Guizhou Provincial Department(YQK[2023]016,ZK[2023]141,[2020]1Y027,GZMUZK[2022]PT01)。

摘　　要：In this study,we reanalyze the top-quark pair production at next-to-next-to-leading order(NNLO)in quantum chromodynamics(QCD)at future e^(+)e^(−)colliders using the Principle of Maximum Conformality(PMC)method.The PMC renormalization scales inαs are determined by absorbing the non-conformalβterms by recursively using the Renormalization Group Equation(RGE).Unlike the conventional scale-setting method of fixing the scale at the center-of-mass energyμ_(r)=√s,the determined PMC scale Q_(⋆)is far smaller than the √sand increases with the √s,yielding the correct physical behavior for the top-quark pair production process.Moreover,the convergence of the pQCD series for the top-quark pair production is greatly improved owing to the elimination of the renormalon divergence.For a typical collision energy of √s=500 GeV,the PMC scale is Q_(⋆)=107 GeV;the QCD correction factor K for conventional results is K∼1+0.1244+0.0102+0.0012−0.0087−0.0011+0.0184−0.0086+0.0002+0.0061−0.0003,where the first error is caused by varying the scaleμr∈[√s/2,2√s]and the second error is from the top-quark massΔm_(t)=±0.7 GeV.After applying the PMC,the renormalization scale uncertainty is eliminated,and the QCD correction factor K is improved to K∼1+0.1507_(−0.0015)^(+0.0015)−0.0057_(−0.0000)^(+0.0001),where the error is from the top-quark massΔm_(t)=±0.7 GeV.The PMC improved predictions for the top-quark pair production are helpful for detailed studies of the properties of the top-quark at future e^(+)e^(−)colliders.

关 键 词：TOP-QUARK lepton colliders Renormalization Group Equation QCD correction 

分 类 号：O572.33[理学—粒子物理与原子核物理]