An improved limit on the electric dipole moment of the Muon at the Fermilab E989 experiment.

费米实验室 E989 实验中对 μ 子电偶极矩的改进限制。

• 批准号: 1751200
• 金额: --
• 依托单位: University of Liverpool
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2016
• 资助国家: 英国
• 起止时间: 2016 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-1751200
• 关键词: improved; limit; electric; dipole; moment

The E989 Muon g-2 experiment is a precision storage ring experiment located at the Fermilab facility. It's primary goal is to measure the muon anomalous magnetic moment to unprecedented precision and thus reduce the systematic uncertainty of au from the previous experiment, the Brookhaven E821 experiment, to a precision of 0.14 parts per million (ppm). A search for a muon electric dipole moment (EDM) will also be performed by the E989 experiment. A permanent EDM for a particle in a non-degenerate state violates both parity (P) and time reversal (T) symmetries and therefore implies CP violation. Unlike parity violation, which is maximal in weak leptonic decays, CP violation has never been observed in the leptonic sector. Given the small observed levels of CP violation (seen only in the decays of neutral Kaons and B-mesons), the standard model (SM) predicts that the EDMs of the leptons are so small that their detection is well beyond experimental capabilities for the foreseeable future. Therefore, any non-zero experimental value would indicate the existence of new physics. The permanent EDM of a muon, if it were to exist, would have a distinctive signature. An EDM would cause a tilt in the muon precession plane away from the vertical orientation and produce tiny vertical oscillations which are 90 degrees out of phase with the au oscillation. Tracking detectors are being constructed at Liverpool University which are capable of measuring these tiny vertical oscillations. I will perform analysis on the experimental spin precession data to look for the signature of an EDM oscillation down to a sensitivity of 10-21e.cm. With the aim of either detecting an EDM signal or improving the experimental limit on the EDM.

E989 Muon g-2实验是位于费米实验室设施的精密储存环实验。它的主要目标是以前所未有的精度测量μ子异常磁矩，从而将Au的系统不确定性从之前的实验Brookhaven E821实验降低到0.14 ppm的精度。E989实验还将对μ子电偶极矩（EDM）进行搜索。非简并态粒子的永久EDM违反了宇称（P）和时间反演（T）对称性，因此意味着CP破坏。不同于宇称破坏，这是最大的弱轻子衰变，CP破坏从来没有观察到轻子部门。考虑到CP破坏的观测水平很小（只在中性K介子和B介子的衰变中看到），标准模型（SM）预测轻子的EDM非常小，以至于在可预见的未来它们的检测远远超出了实验能力。因此，任何非零的实验值都将表明新物理的存在。μ子的永久EDM，如果它存在的话，将有一个独特的签名。EDM将导致μ子进动平面偏离垂直方向的倾斜，并产生与Au振荡相位相差90度的微小垂直振荡。利物浦大学正在建造能够测量这些微小垂直振荡的跟踪探测器。我将对实验自旋进动数据进行分析，以寻找EDM振荡的签名，灵敏度为10 - 21 e.cm。目的是检测EDM信号或改善EDM的实验限制。