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

粒子物理学的标准模型提供了亚原子尺度上基本粒子和力的最新精确描述。 尽管标准模型已经被证明是成功的，但它是不完整的，需要扩展以纳入包括颗粒暗物质在内的新元素。轴子是粒子物理学标准模型的许多扩展中出现的假设粒子，包括动机良好的Peccei-Quinn（PQ）理论。 PQ轴子可以解释测量到的中子电偶极矩的异常小，也是一个有希望的暗物质候选者。轴子共振相互作用探测实验（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实验的开发和建设并启动运行。这种独特的方法为拟议的博士后，研究生和本科生研究人员团队提供了实验原子物理，光泵，核磁共振，低温物理，微制造，磁屏蔽，真空系统和建模技术的广泛培训。这种专业知识的广度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。该实验计划涉及一个多元化的年轻职业研究人员群体，重点是扩大代表性不足的群体的参与。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。轴子和轴子状粒子也产生宏观的P-奇数和（时间反射）T-奇数自旋依赖相互作用，可以在敏感的实验室实验中寻找。ARIADNE实验涉及一个旋转的非磁性物质来产生轴子场，以及一个密集的激光极化3 He核系综来通过NMR（核磁共振）检测轴子场。通过在核自旋进动频率处适当地调制轴子势，可以共振地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得轴子场，因此即使轴子不构成大部分暗物质，这种设置对轴子也很敏感。此外，通过检测轴子与原子核的耦合，一个完全互补的耦合被探索到Sikivie型微波腔“haloscope”实验及其建议的较低和较高频率的扩展所寻求的。这个奖项反映了NSF的法定使命，并被认为是值得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的支持。

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.