Collaborative Research: Axion Resonant InterAction Detection Experiment (ARIADNE) - a Renewal Proposal

粒子物理学的标准模型提供了对亚原子尺度的基本粒子和力的最新准确描述。 尽管标准模型已被证明是成功的，但众所周知它是不完整的，需要扩展以纳入包括颗粒暗物质在内的新元素。轴子是假设的粒子，出现在粒子物理标准模型的许多扩展中，包括动机良好的 Peccei-Quinn (PQ) 理论。 PQ轴子可以解释所测量的中子电偶极矩的异常小，并且也是一个有前途的暗物质候选者。轴子共振相互作用检测实验（ARIADNE）旨在寻找亚毫米范围内原子核之间轴子介导的自旋相关相互作用。该奖项支持合作研究团队完成ARIADNE实验的开发建设并启动运行。这种独特的方法为博士后、研究生和本科生研究人员团队提供了实验原子物理、光泵浦、核磁共振、低温物理、微加工、磁屏蔽、真空系统和建模技术方面的广泛培训。这种广泛的专业知识将为美国劳动力或科学界的基础或应用研究机会做好宝贵的准备。该实验计划涉及多元化的年轻职业研究人员，重点是扩大代表性不足群体的参与。此外，寻找暗物质是一个具有广泛公众吸引力的话题，该小组参与了当地的推广工作。轴子和类轴子粒子还会产生宏观的 P 奇数和（时间反转）T 奇数自旋依赖性相互作用，可以在敏感的实验室实验中寻找这些相互作用。 ARIADNE 实验涉及一个旋转非磁性质量来提供轴子场，以及一个密集的激光偏振 3He 原子核集合，以通过 NMR（核磁共振）检测轴子场。通过在核自旋进动频率下适当调制轴子电势，可以共振增强来自轴子场的信号。随着数据采集阶段的开始，将探索 PQ 轴子和类轴子粒子的新参数空间。与宇宙轴子搜索相反，由于实验使用局部物质来获取轴子场，因此这种设置对轴子敏感，即使它不构成大部分暗物质。此外，通过感测轴子与原子核的耦合，可以探索 Sikivie 型微波腔“haloscope”实验及其提出的低频和高频扩展所寻求的完全互补的耦合。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

The Standard Model of particle physics provides the most current accurate description of the fundamental particles and forces at the subatomic scale. As successful as the Standard Model has proven to be, it is known to be incomplete, requiring extensions to incorporate new elements including particulate dark matter. Axions are hypothesized particles that appear in many extensions of the particle physics Standard Model, including the well-motivated Peccei-Quinn (PQ) theory. The PQ axion may provide explanations for both the anomalous smallness of the measured neutron electric dipole moment, and is also a promising dark matter candidate. The Axion Resonant InterAction DetectioN Experiment (ARIADNE) is designed to search for axion-mediated spin-dependent interactions between nuclei at sub-millimeter ranges. This award supports the collaborative research team to complete the development and construction and initiate operation of the ARIADNE experiment. The unique approach provides the proposed team of postdoctoral, graduate, and undergraduate researchers with a broad training in the techniques of experimental atomic physics, optical pumping, nuclear magnetic resonance, low-temperature physics, micro-fabrication, magnetic shielding, vacuum systems, and modeling. This breadth of expertise will be valuable preparation for opportunities in basic or applied research in the U.S. work force or scientific community. The experimental program involves a diverse group of young career researchers with an emphasis on broadening participation of under-represented groups. In addition, searching for dark matter is a topic with broad public appeal, and the group is involved in local outreach efforts.Axions and axion-like particles also generate macroscopic P-odd and (Time Reversal) T-odd spin-dependent interactions which can be sought in sensitive laboratory experiments. The ARIADNE experiment involves a rotating non-magnetic mass to source the axion field, and a dense ensemble of laser-polarized 3He nuclei to detect the axion field by NMR (nuclear magnetic resonance). The signal from an axion field can be resonantly enhanced by properly modulating the axion potential at the nuclear spin precession frequency. With the start of the data taking stage, new parameter space for the PQ axion and axion-like particles will be explored. In contrast to cosmic axion searches, since the experiment sources the axion field using local matter, this setup is sensitive to the axion even if it does not make up most of the dark matter. Furthermore, by sensing the axion's coupling to nuclei, an entirely complimentary coupling is probed to that sought by Sikivie-type microwave cavity “haloscope'' experiments and their proposed lower- and higher-frequency extensions.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.