Collaborative Research: MRI: Development of Apparatus for the Cold Molecule Nuclear Time-Reversal EXperiment (CeNTREX)

合作研究：MRI：冷分子核时间反转实验装置（CeNTREX）的开发

• 批准号: 2240234
• 负责人: David DeMille
• 金额: $ 51.25万
• 依托单位: University of Chicago
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-15 至 2024-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2240234&HistoricalAwards=false
• 关键词: Collaborative; Research; MRI; Development; Apparatus

This project will support the purchase of equipment and parts needed to construct the apparatus for a new experiment known as CeNTREX, the Cold molecule Nuclear Time-Reversal experiment. CeNTREX is a collaborative effort to detect evidence for new types of fundamental forces and particles, through precise measurements of magnetic resonance signals from nuclei embedded in the polar molecule thallium fluoride. The goal of the CeNTREX experiment is to detect a particular deformation in the shape of an atomic nucleus, known as a nuclear Schiff Moment. This will advance the progress of science because a Schiff Moment along the spin axis of a nucleus can arise only in the presence of fundamental interactions that are not symmetric under reversal of the direction of time. Interactions of this type can be mediated by new, as-yet undetected, particles that are predicted to occur in some theoretical models that extend the current Standard Model of particle physics. A Schiff Moment of size large enough to be detected with the projected sensitivity CeNTREX could indicate the existence of new particles with mass well above that of the heaviest known particles - and even beyond the reach of the Large Hadron Collider (LHC). Hence, CeNTREX will provide one of the few known ways to search for physics beyond the Standard Model associated with particles too massive to be created at the LHC. An experiment with the fundamental discovery potential of CeNTREX can also capture the interest of the general public and raise the level of excitement about science. In addition, design and construction of the CeNTREX apparatus will provide opportunities for training several young scientists in instrumentation development. This type of precision measurement science exposes students to a wide range of intellectual and technical subfields, and provides unusually broad training in experimental physics that benefits development of the scientific workforce of the nation.The existence of an asymmetric charge distribution such as an electric dipole moment (EDM) or a Schiff moment (SM) along a particle's angular momentum axis requires violation of time reversal (T) symmetry, which is equivalent to the more widely-discussed phenomenon of CP violation. Observation of an EDM or SM within a few orders of magnitude of current limits would be evidence for phenomena outside the Standard Model of particle physics theory. Furthermore, there are strong motivations from particle theory and cosmology to expect an EDM or SM in this experimentally-accessible range. Discovery of an EDM or SM could illuminate the mechanism responsible for the observed matter-antimatter asymmetry of the universe, which remains one of the grand challenges of cosmology and particle physics. Moreover, new physics at the TeV scale (the range of energy not being explored at the LHC), carrying new CP-violating phases, naturally give rise to EDM and SM near the current experimental limits. Hence any advance in sensitivity to SMs pushes the frontier of particle physics in a manner complementary to current efforts at the Large Hadron Collider. The CeNTREX apparatus will be developed by integrating a wide array of subsystems - many custom designed and built - including vacuum systems, a molecular beam source, lasers, optical control and detection systems, microwave control and transmission systems, precise magnetic field measurement and control systems, and high voltage systems. The conceptual design of CeNTREX builds from recent advances using the properties of diatomic molecules to amplify signals due to new fundamental forces, and in precisely detecting and manipulating molecules. This novel apparatus will use a cryogenic beam of diatomic molecules to make the world's most sensitive measurement of a SM. Detailed estimates of the first-generation measurement using CeNTREX are projected to yield a 30-fold increase in sensitivity, relative to the current state of the art, to certain types of time-reversal symmetry violating interactions that could be responsible for the cosmological matter-antimatter asymmetry in the Universe.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

该项目将支持购买所需的设备和零件，以建造一个新的实验，称为CeNTREX，冷分子核时间修正实验的装置。CeNTREX是一项合作努力，通过精确测量嵌入极性分子氟化铊中的原子核的磁共振信号，来检测新型基本力和粒子的证据。CeNTREX实验的目标是检测原子核形状的特殊变形，称为核希夫矩。这将推动科学的进步，因为沿着原子核自旋轴的希夫矩沿着只有在存在基本相互作用的情况下才能产生，这种基本相互作用在时间方向逆转的情况下是不对称的。这种类型的相互作用可以由新的、尚未检测到的粒子来介导，这些粒子预计会发生在一些扩展当前粒子物理学标准模型的理论模型中。一个足够大的希夫矩可以用投影灵敏度CeNTREX检测到，这可能表明存在质量远高于已知最重粒子的新粒子-甚至超出了大型强子对撞机（LHC）的范围。 因此，CeNTREX将提供为数不多的已知方法之一，以搜索与大型强子对撞机无法产生的大质量粒子相关的标准模型之外的物理学。 利用CeNTREX的基本发现潜力进行的实验也可以吸引公众的兴趣，提高对科学的兴奋程度。此外，CeNTREX仪器的设计和建造将为培训几位年轻科学家提供仪器开发的机会。这种类型的精确测量科学使学生接触到广泛的知识和技术子领域，并提供异常广泛的实验物理培训，有利于国家科学劳动力的发展。不对称电荷分布的存在，例如电偶极矩（EDM）或希夫矩（SM）沿着粒子角动量轴需要违反时间反转（T）对称性，这相当于更广泛讨论的CP破坏现象。 在电流极限的几个数量级内观察到EDM或SM将是粒子物理学理论标准模型之外的现象的证据。 此外，粒子理论和宇宙学有强烈的动机期望在这个实验可达到的范围内实现EDM或SM。 EDM或SM的发现可以阐明宇宙中观察到的物质-反物质不对称性的机制，这仍然是宇宙学和粒子物理学的重大挑战之一。 此外，TeV尺度（LHC未探索的能量范围）的新物理学，携带新的CP破坏阶段，自然会在当前实验极限附近产生EDM和SM。 因此，对SM敏感性的任何进步都将推动粒子物理学的前沿，与目前在大型强子对撞机上的努力相辅相成。 CeNTREX设备将通过集成广泛的子系统来开发-许多定制设计和建造-包括真空系统，分子束源，激光器，光学控制和检测系统，微波控制和传输系统，精确的磁场测量和控制系统以及高压系统。CeNTREX的概念设计基于最近的进展，利用双原子分子的特性来放大由于新的基本力产生的信号，并精确检测和操纵分子。 这种新的仪器将使用双原子分子的低温束来进行世界上最灵敏的SM测量。 使用CeNTREX的第一代测量的详细估计预计将产生相对于当前技术水平的30倍的灵敏度增加，某些类型的违反时间反演对称性的相互作用，可能是宇宙物质的原因-该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准。