RUI: Calculation of Higher Order Corrections to Positronium Energy Levels

RUI：正电子能级高阶修正的计算

• 批准号: 2011762
• 负责人: Gregory Adkins
• 金额: $ 15万
• 依托单位: Franklin and Marshall College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-08-15 至 2023-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2011762&HistoricalAwards=false
• 关键词: RUI; Calculation; Higher; Order; Corrections; RUI; Calculation; Higher; Order; Corrections

Positronium is the bound system consisting of the electron and its antiparticle, the positron. As such, it forms an “exotic atom”, similar in many ways to traditional simple atoms such as hydrogen and helium, but different because of its unique composition and because of its tendency to annihilate, transforming into pure electromagnetic energy in the form of high-energy photons. Many properties of positronium, such as energy levels and lifetimes, are accessible to high-precision experiments. Positronium properties can also be calculated theoretically to high precision using the methods of bound-state Quantum Electrodynamics (QED) because strong and weak interaction effects are negligible. Consequently, positronium is an ideal system for testing the limits of QED bound state physics and for exploring the consequences of agreement or disagreement between theory and experiment at this high level of precision. The activities involved in calculating the positronium energy levels will be of great educational value to the undergraduate students at Franklin & Marshall College involved as collaborators in that work. The students will learn theoretical methods and techniques of calculation more advanced than those usually encountered at the undergraduate level. They will gain valuable experience by doing the research, by presenting their results at professional meetings, and by publishing their work as co-authors in research journals. Positronium energy levels of low-lying states (n=1 and n=2) have been measured with uncertainties of roughly 1 MHz, and experiments are presently being developed and performed to significantly reduce some of these uncertainties. The 1S-2S transition is of particular interest because it has the smallest natural line-width and thus the greatest potential for improvement. These transition energies and more will be calculated to a new and higher level of precision. The calculations will be based on the low-energy effective quantum field theory NRQED (Non-Relativistic QED), which provides a natural and efficient framework for the study of non-relativistic atoms such as positronium.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

正电子是由电子及其反粒子组成的结合系统，正阳性。因此，它形成了一个“异国原子”，在许多方面与传统的简单原子（如氢和氦气）相似，但由于其独特的成分和倾向于歼灭，以高能量照片的形式转化为纯电磁能。阳性的许多特性，例如能量水平和寿命，可以进行高精度实验。也可以使用结合状态量子电动力学（QED）的方法计算出理论上的正电子性能，因为强相互作用效应可以忽略不计。因此，阳性是测试QED结合状态物理学限制并探索理论与实验之间一致性或分歧的后果的理想系统。计算正能量水平的活动对富兰克林和马歇尔学院的本科生具有巨大的教育价值，这是该工作的合作者。与本科生通常相比，学生将学习理论方法和计算技术更先进的方法。他们将通过进行研究，在专业会议上展示结果，并在研究期刊上发表合着者来获得价值经验。低洼状态（n = 1和n = 2）的阳性能量水平已通过大约1 MHz的不确定性进行了测量，并进行了实验，并进行了实验，以显着减少其中的某些不确定性。 1S-2S的过渡特别令人感兴趣，因为它具有最小的自然线宽度，因此最大的改进潜力。这些过渡能和更多的能量将计算为新的和更高的精度。该计算将基于低能量有效的量子场理论NRQED（非权威主义QED），该理论提供了一个自然而有效的框架，用于研究非权威主义原子（例如正面），例如正面。该奖项反映了NSF的法定任务，并通过使用基金会的知识优点和广泛的范围来评估，认为NSF的法定任务是宝贵的。