Theory of atomic processes and interactions

原子过程和相互作用理论

• 批准号: 5912-2011
• 负责人: Drake, Gordon
• 金额: $ 5.03万
• 依托单位: University of Windsor
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=568427
• 关键词: Theory; atomic; processes; interactions

The unifying theme of this proposal is the development of new measurement tools through the combined application of both high precision theory and experiment to atoms. Two examples are a significant new value for the fine structure constant, which is one of the fundamental constants of nature, and table-top measurements of the size of exotic atomic nuclei. Recent successes at Argonne (U.S.), GSI (Germany) and TRIUMF (Canada) have focused on the so-called neutron-rich "halo" nuclei with extra planetary neutrons, such as He-6. The significance of the results is that they enable one to distinguish amongst the various theoretical models proposed for the effective forces holding the nucleus together. By studying structures that fall apart easily, we learn about the forces holding them together. A fascinating new project for the future involves a search for new physics beyond the standard model of elementary particles, as revealed by angular correlations following beta decay of the halo nucleus. Two recent advances have made these initiatives possible. First, our work has yielded unprecedented levels of accuracy in calculating the properties of atoms from first principles. Some of this requires the high performance computing facilities of SHARCNET, together with fundamental advances in methods to calculate essential corrections due to relativity and quantum electrodynamics. I have formed an international collaboration of other researchers in Canada and China to carry out this work, with the help of dedicated resources from SHARCNET. Second, we work in close collaboration with the top experimental groups around the world who perform measurements of exquisite accuracy and sensitivity. The ability to trap and study just a single atom plays a key role. A long sequence of joint papers published in Physical Review Letters has resulted from these collaborations. Our theoretical results dominate the literature in this area, and they are providing the motivation for several experimental groups around the world to advance the state-of-the-art for high precision laser metrology.

本提案的统一主题是通过将高精度理论和实验结合应用于原子来开发新的测量工具。两个例子是精细结构常数的重要新值，这是自然界的基本常数之一，以及对外来原子核大小的桌面测量。美国阿贡、德国GSI和加拿大TRIUMF最近的成功都集中在所谓的富含中子的“晕”核上，比如氦-6。这些结果的意义在于，它们使人们能够区分为把原子核结合在一起的有效作用力而提出的各种理论模型。通过研究容易分解的结构，我们了解了使它们结合在一起的力量。一个引人入胜的未来新项目涉及寻找超越基本粒子标准模型的新物理学，正如光环核衰变后的角相关性所揭示的那样。