Argon Crystals for the Electron Electric Dipole Moment (eEDM) Search with the EDM^3 Collaboration

提出的研究是为了寻找永久电子（e-）电偶极矩（EDM）。e-在经典物理图像中是一个点粒子，但物理学预测它附近的电荷是不对称的。在电场中，例如在极性分子中，检测到eEDM的进动或摆动，将证实预期的，但难以捉摸的eEDM。为了探索这种影响，需要对长时间（以岁差时间为特征）进行许多e-（改进的统计数据）观察。ACME II合作测量表明，eEDM低于1.1*10^—29 e-cm。挑战在于电火花加工的物理尺寸很小，其测量将需要开发新技术。我们最近建立的EDM^3（使用矩阵内分子的电偶极子测量）合作的预测灵敏度将发现eEDM或将其限制在<10^-34 ecm的水平，提高了10^5倍。我对EDM^3的独立研究贡献将为极性分子固定的氩（Ar）晶体生长提供理想的衬底。具体来说，“发现”项目的短期目标是：(1)从晶体形式的液态氩中产生高纯度的低温氩固体；(2)进行晶体学测量，确认其为单片晶体，缺陷和杂质含量要求较低；(3)操作该低温晶体，将其运送到单独的设备中，在此设备中，极性分子在该想法衬底上的附加晶体生长过程中沉积，用于EDM^3目标。这些目标都是为了实现EDM^3目标，在EDM^3目标中，一种设备正在开发中，用于观察在Ar固体中冻结的第一个极性分子。在这里，氩气被冻结在蓝宝石衬底上，并冻结在一个未知的，随机的方向，由于蓝宝石表面电位。EDM^3物镜需要一个圆柱形，直径厘米，完美无瑕，嵌入极性分子的Ar晶体。在e附近发现电荷的不对称性将导致永久的eEDM，这一发现将是突破性的，它缩小了描述宇宙的可能物理模型的范围，并提供了导致宇宙中观察到的物质-反物质不对称性的新粒子或相互作用的证据。我们的新方法将通过将分子固定在冷冻氩晶体中来增加观察的数量和观察的持续时间。我们的小型实验室设备是新颖的：检测这种微小尺寸的测量方法探测的能量尺度超出了高能加速器的范围，使我们的研究与欧洲核子研究中心的大型强子对撞机实验具有竞争力，但成本只占加拿大大学的一小部分。该项目将使10名本科生和7名毕业生接受高科技领域的培训，为当今行业的职业发展提供理想的机会。我们研究的成功将为实现迄今为止最灵敏的eEDM测量奠定基础。

The proposed research is toward the search for the permanent electron (e-) electric dipole moment (EDM). The e- is a point particle in the classical physics picture but physics predicts an asymmetry in the charge near it. Detecting the precession or wobble of the eEDM in an electric field, in polar molecules for example, will confirm the expected, yet elusive, eEDM. To probe for this effect, many e- (improved statistics) observed for long periods (characterized by precession time) are required. Measurements by the ACME II collaboration indicate an eEDM below 1.1*10^--29 e-cm. The challenge is that the physical size of the e EDM is tiny and its measurement will require development of new techniques. The projected sensitivity of our recently established EDM^3 (Electric Dipole Measurements using Molecules within a Matrix) collaboration will find the eEDM or limit it at a level of <10^-34 ecm, a 10^5 times improvement. My independent research contribution to the EDM^3 will provide the ideal substrate for Argon (Ar) crystal growth in which the polar molecules are fixed. Specifically, the short-term objectives of this Discovery application are to: (1) produce highly pure cryogenic Ar solids from liquified Ar in a crystal form; (2) make crystallographic measurements to confirm it is a monolithic crystal with the required low defect and impurity content; and (3) manipulate this cryogenic crystal transporting it into separate apparatus where the polar molecules are deposited during additional crystal growth on this idea substrate for EDM^3 goals. These objectives are toward EDM^3 goals where an apparatus is under development to observe the first polar molecules frozen in an Ar solid. Here argon is frozen on a sapphire substrate and freezes in an unknown, random orientation due to the sapphire surface potentials. A cylindrical, cm diameter, flawless, Ar crystal with embedded polar molecules is to be needed for EDM^3 objectives. Finding an asymmetry in the charge near the e would lead to a permanent eEDM, the discovery of which would be ground-breaking, narrowing the range of possible physics models describing the universe, and providing evidence of new particles or interactions that lead to the observed matter--antimatter asymmetry in the universe. Our new approach will increase the e number observed and the duration of time they are observed by fixing the molecules in a crystal of frozen Ar. Our small laboratory apparatus is novel: measurements that detect this tiny size probe energy scales beyond the reach of high energy accelerators, making our research competitive with LHC experiments at CERN but at a tiny fraction of the cost and housed at a Canadian University. This project will enable 10 undergraduates and 7 graduates to receive training in high tech fields ideal for careers in today's industries. The success of our research will cement the way to achieve the most sensitive measurement yet of the eEDM.