RUI: Tests of Fundamenal Symmetries using Hg, Cs and GdIG

RUI：使用 Hg、Cs 和 GdIG 进行基本对称性测试

• 批准号: 0244913
• 负责人: Larry Hunter
• 金额: $ 34.07万
• 依托单位: Amherst College
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-01 至 2007-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0244913&HistoricalAwards=false
• 关键词: RUI; Tests; Fundamenal; Symmetries; using

This RUI award funds two projects at Amherst College. The first project is a continuation of an experiment to test Local Lorentz Invariance (LLI) and CPT invariance. LLI is the notion that the laws of physics are the same in all locally inertial frames. This is one of the fundamental postulates of the theory of Relativity. CPT is the product of the discrete symmetries charge conjugation, parity and time. No violation of either LLI or CPT has ever been observed. Much of our understanding of fundamental physics would have to be radically altered if a violation is observed. The experiment compares the relative precession frequencies of Hg and Cs magnetometers as a function of the orientation of an applied magnetic field with respect to the "fixed stars". The second project involves the investigation of the possibility of using a solid-state system (gadolinium iron garnet) to measure the electron electric-dipole moment (edm). Most particle physics models that go beyond the Standard Model (such as Supersymmetry) predict an electron edm very near the current experimental bound (about 10-27 e-cm). Thus far, all attempts to find the electron edm are consistent with zero. Present estimates of the proposed experiment's sensitivity suggest that it should be possible to detect an electron edm as small as 10-29 e-cm. If an electron edm is observed, it would constitute a violation of time-reversal symmetry and be evidence for new physics beyond the Standard Model. The broader impacts of the program relate to important implications for particle physics, but also provide a broad and flexible training for future scientists, especially at the undergraduate level.

该RUI奖资助阿默斯特学院的两个项目。第一个项目是测试局部洛伦兹不变性（LLI）和CPT不变性的实验的延续。LLI是物理定律在所有局部惯性系中是相同的概念。这是相对论的基本假设之一。CPT是离散对称性电荷共轭、宇称和时间的乘积。没有观察到违反LLI或CPT的情况。如果观察到违反，我们对基础物理学的许多理解将不得不从根本上改变。该实验比较了Hg和Cs磁强计的相对进动频率，作为相对于“恒星”的施加磁场方向的函数。第二个计画是探讨使用固态系统（钆铁石榴石）来量测电子电偶极矩（edm）的可能性。大多数超越标准模型的粒子物理模型（如超对称）预测电子edm非常接近当前的实验边界（约10-27 e-cm）。到目前为止，所有寻找电子edm的尝试都与零一致。目前对实验灵敏度的估计表明，应该有可能探测到小到10-29 e-cm的电子edm。如果观察到电子edm，它将构成对时间反演对称性的破坏，并成为超越标准模型的新物理学的证据。该计划的更广泛的影响涉及粒子物理学的重要影响，但也为未来的科学家，特别是在本科阶段提供了广泛而灵活的培训。