Ultracold Neutron Electric Dipole Moment Experiment

超冷中子电偶极矩实验

• 批准号: SAPPJ-2019-00031
• 负责人: Martin, Jeffery
• 金额: $ 40.07万
• 依托单位: University of Winnipeg
• 依托单位国家: 加拿大
• 项目类别: Subatomic Physics Envelope - Project
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=718505
• 关键词: Ultracold; Neutron; Electric; Dipole; Moment

Our experiment aims to measure the neutron electric dipole moment (nEDM) more precisely than ever before. A new measurement of the nEDM will place even tighter constraints on theories involving new sources of Charge-Parity (CP) violation beyond the standard model. It is believed these are required in order to explain the predominance of matter over antimatter (baryon asymmetry) in the universe today. Quite generically, the experiment will constrain broad classes of new physics scenarios which do not conserve CP. A new measurement also could impact a long-standing mystery in the standard model, involving the appararent lack of CP violation arising from the strong force. A discovery of a non-zero nEDM would be a major discovery, because it would shed light on a broad range of theories. A key tool in this search is a new source of ultracold neutrons (UCN). UCN are slow moving neutrons that can be stored in material, magnetic, and gravitational bottles. Once they've been confined using such methods, their properties can be studied very carefully to search for deviations from expectations based on the standard model of particle physics. Our scientific collaboration is named the TUCAN (TRIUMF Ultracold Advanced Neutron) collaboration. In the past three years, we have completed a new source of UCN in Canada (at TRIUMF, Vancouver, BC) with the help of collaborators from Japan. New funds for upgrades to the UCN source and for the construction of a new neutron EDM experiment have been secured from the Canada Foundation for Innovation and partner contributions including a substantial contribution from Japan. Once the upgrades are complete, the source is projected to provide the highest density of UCN in the world. The source will be used to advance fundamental physics experiments to unprecedented levels of precision. Our activities over the next three years will involve the completion of the UCN source upgrade and the nEDM experiment construction. We will also use the existing UCN source at TRIUMF for experiments aimed at answering critical questions for the overall success of the experiment.

我们的实验旨在比以往更精确地测量中子电偶极矩（nEDM）。 一个新的测量nEDM将放置更严格的约束理论，涉及新的来源的电荷宇称（CP）违反超出标准模型。 据信，这些都是为了解释当今宇宙中物质对反物质的优势（重子不对称性）所必需的。 一般来说，该实验将限制不守恒CP的新物理场景的广泛类别。 一个新的测量方法也可能会影响标准模型中一个长期存在的谜团，即强作用力明显缺乏CP破坏。 非零nEDM的发现将是一个重大发现，因为它将揭示广泛的理论。 这项研究的一个关键工具是一种新的超冷中子源（UCN）。 UCN是缓慢移动的中子，可以储存在物质、磁性和重力瓶中。 一旦使用这种方法限制它们，就可以非常仔细地研究它们的性质，以寻找与基于粒子物理学标准模型的预期的偏差。 我们的科学合作被命名为TUCAN（TRIUMF超冷先进中子）合作。 在过去的三年里，在日本合作者的帮助下，我们在加拿大完成了UCN的新来源（在不列颠哥伦比亚省温哥华的TRIUMF）。 用于升级UCN源和建造一个新的中子EDM实验的新资金已从加拿大创新基金会和包括日本大量捐款在内的伙伴捐款中获得。 一旦升级完成，该源预计将提供世界上最高密度的UCN。 该源将用于将基础物理实验推进到前所未有的精度水平。 我们未来三年的活动将包括完成UCN源升级和nEDM实验建设。 我们还将使用TRIUMF现有的UCN源进行实验，旨在回答实验整体成功的关键问题。