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

这项研究将为铯的宇称非守恒（PNC）测量提供一个长期寻求的独立检查，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），对我们理解原子和核层面的物质至关重要。新的更高精度的实验室测量将允许更精确地确定弱电荷，这是标准模型中的基本量。更重要的是在不同的超精细跃迁上测量PNC相互作用，这将探测高阶效应，如核模拟矩。先前对原子系统中核子-核子散射的测量产生了耦合常数的约束，这些约束与高能散射测量产生的约束不一致，而提出的测量旨在帮助解决这些差异。这项工作将(1)促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)为物理和工程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，学生在实验室还学习重要的技术技能，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水平的教育，促进科学和工程的多样性，并将研究与教育相结合。本科生在PI实验室的参与是这个项目的一个积极方面。

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.