arXiv 0804.37062008-04-23hep-ex

LHC顶夸克电弱产生的研究

Investigation of Electroweak Production of the Top Quark at the LHC

Akira Shibata

备注：: 176 pages

摘要：

本论文对在大型强子对撞机上测量顶夸克的电弱产生的前景进行了研究。顶夸克的研究是一个非常热门的话题，因为我们预计在大型强子对撞机上会有大量的顶夸克，这将使我们能够对顶夸克的性质进行精确的测量。t通道“单顶”是一种相对罕见的顶生产模式，但有了它，我们可以探测自旋结构的Wtb顶点在弱相互作用在一个前所未有的能量尺度通过测量的顶部极化。分析战略和计算工具得到了广泛的开发和测试。这项研究是使用蒙特卡洛发生器模拟的信号和背景事件进行的，其中许多是为LHC分析新开发的。对ATLAS探测器进行了全面和快速的模拟，以获得对测量灵敏度的真实估计。为ATLAS协作开发了一个新的成熟分析框架“EventView”，以在第一级分析中处理这些数据。开发参数化顶点标记以估计该分析的背景水平，并使用极大似然拟合来精确提取顶部偏振。在大型强子对撞机的高能强子环境中，需要仔细考虑可能的实验和理论系统误差的估计。研究了系统误差的重要组成部分，并对主要贡献进行了评价。

英文摘要：

This thesis presents a study of the prospects of measuring electroweak production of the top quark at the LHC. The study of the top quark is a highly topical subject as we expect significant numbers of top quarks at the LHC which will enable us to conduct precision measurements of the properties of the top. The t-channel "single top" is a relatively rare mode of top production but with it we can probe the spin structure of the Wtb vertex in the weak interaction at an unprecedented energy scale through the measurement of the top polarisation. Analysis strategies and computing tools were developed and tested extensively. The study was performed using the signal and background events modelled with Monte Carlo generators, many of which have been newly developed for the LHC analyses. Full and fast simulation of the ATLAS detector was performed to obtain realistic estimates of the sensitivity of the measurements. A new fully fledged analysis framework, "EventView" was developed for the ATLAS collaboration to process these data at the first level of analysis. Parameterised vertex tagging was developed to estimate the level of background for this analysis and a maximum likelihood fit was used for the precise extraction of the top polarisation. In the high energy hadronic environment at the LHC, the estimation of possible systematic errors, both experimental and theoretical, needs to be carefully considered. Important elements of the systematic errors were investigated and the main contributions were evaluated.

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。

摘要：

英文摘要：

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