arXivDaily arXiv每日学术速递 周一至周五更新
北美退伍军人节(Veterans Day),12 日无更新
arXiv 1709.09407hep-ex
收藏

用ATLAS探测器测量$\sqrt{s}=8$ TeV的PDMATHAAB碰撞中$t\bar{t}$产生的轻子微分分布和顶夸克质量

Measurement of lepton differential distributions and the top quark mass in $t\bar{t}$ production in $pp$ collisions at $\sqrt{s}=8$ TeV with the ATLAS detector

ATLAS Collaboration

摘要:

本文给出了在大型强子对撞机(LHC)ATLAS实验中记录的$\sqrt{s}=8$ TeV $pp$的20.2 fb $^{-1}$中产生的双轻子$t\bar{t}$事例的单轻子和双轻子运动学分布。绝对和归一化微分截面测量,使用事件与相反电荷$eμ$对和一个或两个$b$标记的射流。横截面的测量在一个基准区域对应的检测器接受轻子,并进行比较,从各种Monte Carlo事件发生器的预测,以及固定阶QCD计算,探索胶子部分子分布函数的灵敏度的横截面。一些分布对顶夸克极质量也很敏感; NLO固定阶预测与所有测量分布的组合拟合产生了$m_t^{\rm pole}=173.2\pm 0.9\pm0.8\pm1.2$ GeV的顶夸克质量值,其中三个不确定性来自数据统计,实验系统学和理论来源。

英文摘要:

This paper presents single lepton and dilepton kinematic distributions measured in dileptonic $t\bar{t}$ events produced in 20.2 fb$^{-1}$ of $\sqrt{s}=8$ TeV $pp$ collisions recorded by the ATLAS experiment at the LHC. Both absolute and normalised differential cross-sections are measured, using events with an opposite-charge $eμ$ pair and one or two $b$-tagged jets. The cross-sections are measured in a fiducial region corresponding to the detector acceptance for leptons, and are compared to the predictions from a variety of Monte Carlo event generators, as well as fixed-order QCD calculations, exploring the sensitivity of the cross-sections to the gluon parton distribution function. Some of the distributions are also sensitive to the top quark pole mass; a combined fit of NLO fixed-order predictions to all the measured distributions yields a top quark mass value of $m_t^{\rm pole}=173.2\pm 0.9\pm0.8\pm1.2$ GeV, where the three uncertainties arise from data statistics, experimental systematics, and theoretical sources.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑