Atomic parity violation in muonic X-rays

由于Muon波函数和原子核有很大的重叠，因此Muon原子是研究Muon和原子核之间相互作用的很好的实验室。辐射原子跃迁，即所谓的缪子X射线，可以提供有关原子核大小的准确信息。此外，波函数的大重叠增加了该系统对短程相互作用的灵敏度，特别是在缪子X射线中引起原子宇称破坏效应的弱中性电流。然而，关于低能量下中性电流效应的数据很少，而且没有关于µ子的数据。新的，特定于Muon的相互作用可能会引入相同量级的宇称破坏效应，或者比粒子物理标准模型中预期的幅度更大。这些相互作用在一定程度上是由最近Muon数据中超越标准模型的物理暗示所驱动的。在这个提议中，我们关注的是Muon锌中相反宇称2S和2P原子能级的混合。这一建议的范围是：(A)对锌中的单光子2S-1S跃迁进行干净的测量，确定其在原子级联中的分支比，并充分了解所有相关背景。为此，计划在瑞士的保罗·谢勒研究所使用高纯度锗探测器阵列进行两次测量。今年批准了第一束时间为两个弱的。(B)为未来的缪子原子的原子宇称破坏实验(APV)进行优化的实验设计，并确定其超出标准模型物理范围。(C)为226Ra的装药半径测量做出重大贡献。这项测量将作为即将到来的用单一镭离子进行的原子宇称破坏实验的重要输入。(D)美因茨约翰尼斯·古滕贝格大学的一篇博士论文。

Muonic atoms are an excellent laboratory to study the interaction between the muon and the atomic nucleus as there is a large overlap of the muon wave function and the nucleus. Radiative atomic transitions, so-called muonic X-rays, yield accurate information on the size of the nucleus. In addition, the large overlap of the wave functions increases the sensitivity of this system for short-range interactions, in particular weak neutral currents inducing atomic parity violating effects in muonic X-rays. Data on neutral current effects at low energies is sparse however, and there is none with muons. New, muon specific interactions may introduce parity violating effects of the same order or larger than the amplitudes expected in the Standard Model of particle physics. These interactions are in part motivated by hints of physics beyond the Standard Model in recent muon data.In this proposal, we focus on the mixing of the opposite parity 2S and 2P atomic levels in muonic zinc. The scope of this proposal is:(a) to make a clean measurement of the single photon 2S-1S transition in zinc, determine its branching ratio in the atomic cascade, and to fully understand all relevant backgrounds. For this purpose, two measurements with a high-purity germanium detector array are planned at the Paul Scherrer Institute in Switzerland. A first beam time of two weak was approved this year.(b) to make an optimized experimental design for a future atomic parity violation experiment (APV) with muonic atoms, and to determine its beyond the Standard Model physics reach. (c) to make a significant contribution to the charge radius measurement of 226Ra. This measurement will serve as an important input for the upcoming atomic parity violating experiment with a single radium ion. (d) one PhD thesis at the Johannes Gutenberg University of Mainz.