Measurements of the Parity Non-Conservation Amplitude in Atomic Cesium for Improved Tests of the Standard Model and Beyond

原子铯宇称非守恒振幅的测量，用于改进标准模型及其他模型的测试

• 批准号: 0970041
• 负责人: Daniel Elliott
• 金额: $ 51.5万
• 依托单位: Purdue University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-15 至 2014-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0970041&HistoricalAwards=false
• 关键词: Measurements; Parity; Non; Conservation; Amplitude

This research will provide a long-sought independent check of the Parity Non-Conserving (PNC) measurement in cesium, and especially of the nuclear spin dependence of these measurements. Tests of the Standard Model, the theoretical description of the physical world that unifies two of the four fundamental forces (the weak forces and electromagnetic forces), are critical to our understanding of matter at the atomic and nuclear level. New laboratory measurements of higher precision will allow for an even more precise determination of the weak charge, a fundamental quantity within the Standard Model. Even more important will be measurements of the PNC interaction on the different hyperfine transitions, which will probe higher-order effects such as the nuclear anapole moment. Prior measurements of nucleon-nucleon scattering in atomic systems have produced constraints of coupling constants that are at odds with those from high-energy scattering measurements, and the proposed measurements are designed to help resolve these discrepancies. This work will (1) advance our understanding of interactions beyond those typically encountered in atomic physics, (2) lead to advances in detection of weak interactions, and (3) provide educational opportunities for graduate and undergraduate students in disciplines of Physics and Engineering. In addition to mastery of topics of current interest, students in the laboratory learn important technical skills such as optics and lasers, electronics, data analysis, and computer programming. The PI is committed to education at the graduate and undergraduate level, promoting diversity in science and engineering, and integrating research and education. Participation by undergraduate students in the PI's laboratory is an active facet of this program.

这项研究将提供一个长期寻求的独立检查宇称非守恒（PNC）测量铯，特别是这些测量的核自旋依赖性。标准模型是对物理世界的理论描述，它统一了四种基本力中的两种（弱力和电磁力），对我们在原子和原子核水平上理解物质至关重要。更高精度的新实验室测量将允许更精确地确定弱电荷，这是标准模型中的一个基本量。更重要的是测量PNC相互作用对不同的超精细跃迁，这将探测更高阶的影响，如核的anapole矩。原子系统中核子-核子散射的先前测量已经产生了与高能散射测量不一致的耦合常数的约束，并且所提出的测量旨在帮助解决这些差异。这项工作将（1）推进我们对原子物理学中通常遇到的相互作用的理解，（2）导致弱相互作用检测的进步，（3）为物理学和工程学学科的研究生和本科生提供教育机会。除了掌握当前感兴趣的主题外，实验室的学生还学习重要的技术技能，例如光学和激光、电子学、数据分析和计算机编程。PI致力于研究生和本科教育，促进科学和工程的多样性，并整合研究和教育。PI实验室的本科生参与是该计划的一个积极方面。