Determination of the Kinematics of the Qweak Experiment and Investigation of an Atomic Hydrogen Moller Polarimeter
Determination of the Kinematics of the Qweak Experiment and Investigation of an Atomic Hydrogen Moller Polarimeter
复制标题
Qweak实验运动学的确定和原子氢莫勒旋光计的研究
DOI：
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发表时间：
2018
期刊：
影响因子：
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通讯作者：
V. Gray
中科院分区：
文献类型：
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作者：
V. Gray
Qweak实验通过精确测量质子的弱电荷（QpW）来检验标准模型。这是通过测量极化电子散射非极化质子的宇称破坏不对称性来完成的。测量的宇称破坏不对称性与从电子到质子的四动量转移（Q）成正比。从测量的不对称性中提取QpW需要精确的Q测定。Qweak实验的Q2 = 24.8± 0.1 m（GeV），达到了不确定度≤ 0.5%的目标。根据测量的不对称性和Q，QpW被确定为0.0719± 0.0045，这与标准模型预测非常一致。这为可能的“新物理学”设定了7.5 TeV的下限。本文主要介绍了Q弱实验中的Q值分析。未来类似于Qweak实验的宇称违反电子散射实验将测量高精度的不对称性，以检验标准模型。这些测量将需要测量光束偏振至低于0.5%的精度。目前，电子束极化是通过铁磁箔的莫勒散射或通过使用康普顿散射来测量的，这两种方法都可能存在达到这种精度的问题。提出了一种新型的原子氢莫勒偏振计，通过极化的单原子氢气的莫勒散射来测量电子束的偏振。本文描述了氢原子穆勒偏振计的蒙特卡罗模拟的发展和初步分析。目录鸣谢。. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .四奉献精神。. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi表格列表。. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .七、图表清单。. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viii方程列表。. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . X
The Qweak experiment has tested the Standard Model through making a precise measurement of the weak charge of the proton (QpW). This was done through measuring the parity-violating asymmetry for polarized electrons scattering off of unpolarized protons. The parity-violating asymmetry measured is directly proportional to the four-momentum transfer (Q) from the electron to the proton. The extraction of QpW from the measured asymmetry requires a precise Q determination. The Qweak experiment had a Q 2 = 24.8± 0.1 m(GeV) which achieved the goal of an uncertainty of ≤ 0.5%. From the measured asymmetry and Q, QpW was determined to be 0.0719± 0.0045, which is in good agreement with the Standard Model prediction. This puts a 7.5 TeV lower limit on possible “new physics”. This dissertation describes the analysis of Q for the Qweak experiment. Future parity-violating electron scattering experiments similar to the Qweak experiment will measure asymmetries to high precision in order to test the Standard Model. These measurements will require the beam polarization to be measured to sub-0.5% precision. Presently the electron beam polarization is measured through Møller scattering off of a ferromagnetic foil or through using Compton scattering, both of which can have issues reaching this precision. A novel Atomic Hydrogen Møller Polarimeter has been proposed as a non-invasive way to measure the polarization of an electron beam via Møller scattering off of polarized monatomic hydrogen gas. This dissertation describes the development and initial analysis of a Monte Carlo simulation of an Atomic Hydrogen Møller Polarimeter. TABLE OF CONTENTS Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv Dedication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viii List of Equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . x