Phase 1 nEDM experiment support

第 1 阶段 nEDM 实验支持

• 批准号: SAPEQ-2017-00009
• 负责人: Mammei, Russell
• 金额: $ 3.4万
• 依托单位: University of Winnipeg
• 依托单位国家: 加拿大
• 项目类别: Subatomic Physics Envelope - Research Tools and Instruments
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=616794
• 关键词: Phase; nEDM; experiment; support

The search for permanent electric dipole moments (EDM) in particles or atoms plays a critical role in the development of the "new" Standard Model (SM) of particle physics. The current SM of particle physics is the theory that classifies all the known subatomic particles and their interactions. Despite huge experimental success, such as existence of the quarks and the Higgs Boson, it fails at explaining some big questions such as: What is Dark Matter? and Why is there more matter than antimatter in the universe? These questions have motivated the search for extensions to the Standard Model, which predict the existence of new particles and/or new forces of nature. Many of these theoretical extensions naturally predict the existence of a finite permanent EDM of a particle or atom many orders of magnitude larger than allowed by the current SM. If found, it would be heralded as a source of new physics and provide much needed guidance toward a "new" standard model of particle physics. The most precise and significant limits have been set on the EDM of the neutron, the electron, and the Hg-199 atom, leading to tight constraints or disproving many theoretical extensions of the SM. We aim to improve the limits on the (or find a finite) electric dipole moment of the neutron. Through our international collaboration with Japan, we are building a next generation ultracold neutron (UCN) source at TRIUMF, Canada's National Laboratory for Nuclear and Particle Physics. The flagship experiment utilizing this source will search for the neutron electric dipole moment. The TRIUMF UCN source will be based on superfluid He-II, which does not suffer the same UCN production limitations of previous sources and builds upon on a 15 year development program in Japan. The experiment will occur in two phases: Phase I involves the installation and running of a prototype UCN source and nEDM apparatus, built in Japan and moved to TRIUMF, while Phase II includes an upgraded UCN source and nEDM experiment aimed at improving the current best measurement of the nEDM by a factor of 30. This grant request focuses on essential equipment required to fully integrate the Phase I nEDM apparatus and UCN source, from Japan, at TRIUMF. Many components from Japan will be reused but due to the different experimental conditions at TRIUMF compared to that in Japan, we require more UCN guides, a new nEDM cell valve, and an external magnetic field compensation system. Another key aspect of neutron EDM experiments is the control of systematic effects related to magnetic fields and to address this for Phase I we are developing a Hg-199 comagnetometer. This instrument is being led by our University of British Columbia colleagues, where equipment and materials requested herein will allow the rapid progress of this system.

在颗粒或原子中寻找永久性电偶极矩（EDM）在粒子物理的“新”标准模型（SM）的开发中起着至关重要的作用。当前粒子物理的SM是将所有已知的亚原子粒子及其相互作用分类的理论。尽管实验成功，例如夸克和希格斯玻色子的存在，但它还是无法解释一些大问题，例如：什么是暗物质？为什么在宇宙中比反物质还要多？这些问题促使人们寻找对标准模型的扩展，该模型预测了新粒子和/或自然力量的存在。这些理论扩展中的许多自然可以预测粒子或原子的有限永久性EDM的存在，许多数量级比当前SM所允许的大。如果发现，它将被预示为新物理学的来源，并为粒子物理的“新”标准模型提供了急需的指导。 最精确，最明显的限制已设置在中子，电子和HG-199原子的EDM上，导致严格的约束或反驳SM的许多理论扩展。我们旨在提高中子（或找到有限的）电偶极矩的极限。通过与日本的国际合作，我们正在加拿大国家核和粒子物理实验室Triumf建立下一代超级中子（UCN）来源。利用此源的旗舰实验将搜索中子电偶极矩。 Triumf UCN来源将基于Superfluid HE-II，该国际II不会遭受以前来源的UCN生产限制，并在日本的15年开发计划上建立在基础上。该实验将分为两个阶段：I期涉及在日本建造的原型UCN源和NEDM设备的安装和运行，而II期则包括升级的UCN源和NEDM实验，旨在提高NEDM当前最佳测量值30倍。 该赠款请求重点是完全整合来自日本Triumf的I阶段NEDM设备和UCN来源所需的基本设备。将重复使用来自日本的许多组件，但是由于凯旋的实验条件与日本的实验条件不同，我们需要更多的UCN指南，新的NEDM细胞阀和外部磁场补偿系统。中子EDM实验的另一个关键方面是控制与磁场有关的系统效应，并为此解决了这一问题，我们正在开发HG-199 comagnetometer。该乐器由我们不列颠哥伦比亚大学的同事领导，此处要求的设备和材料将允许该系统的快速进步。