Collaborative Research: Axion Resonant InterAction DetectioN Experiment (ARIADNE) -a Continuation Proposal

多次天文观测已经证实，宇宙中大约85%的物质不是由已知粒子构成的。破译这种所谓的暗物质的本质对宇宙学、天体物理学和高能粒子物理学至关重要。粒子物理学中最令人兴奋的任务之一是寻找超越粒子物理学标准模型的新粒子。标准模型的扩展不仅预测了具有大质量的新粒子，而且还预测了一些质量非常小的粒子。这样的候选者就是轴子，它被引入来解释量子色动力学中电荷宇称（CP）破坏的小性，而且它也被证明是宇宙中暗物质组成的主要候选者。轴子共振相互作用探测实验（ARIADNE）旨在搜索亚毫米范围内原子核之间轴子介导的自旋依赖相互作用。该实验采用旋转的非磁性物质作为轴子场的源，用密集的激光极化氦-3核系综通过核磁共振探测轴子场。在参与这项研究的过程中，一个由博士后、研究生和本科生组成的团队将在实验原子物理、光泵浦、核磁共振、低温物理、微制造、磁屏蔽、真空系统和建模技术方面进行广泛的培训。这将是基础或应用研究工作的宝贵准备，无论是在美国或国际工作队伍或科学界。在核自旋进动频率处适当调节轴子势，可以使轴子场的信号共振增强。该合同的目标是完成实验的建设，使其通过调试阶段，在此期间将对可能的系统进行评估，并开始早期数据采集阶段，探索PQ轴子的新参数空间。该方法有可能将以前的轴子实验和天体物理界限提高几个数量级，并深入探索理论上有趣的PQ轴子体系。这个实验对更奇异的类轴子粒子也很敏感。新方法最终可以超越目前实验室对自旋依赖的短程力的限制，最高可达8个数量级，并且可以在10微ev和10毫伏ev之间的轴子质量范围内将实验室/天体物理的综合限制提高10^4倍，深入探索传统的“pq -轴子窗口”。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Multiple astronomical observations have established that about 85% of the matter in the universe is not made of known particles. Deciphering the nature of this so-called Dark Matter is of fundamental importance to cosmology, astrophysics, and high-energy particle physics. One of the most exciting quests in particle physics is the search for new particles beyond the Standard Model of particle physics. Extensions of the Standard Model predict not only new particles with large masses but also some with very small masses. Such a candidate is the axion, which has been introduced to explain the smallness of Charge-Parity (CP) violation in Quantum Chromodynamics and which turns out to also be a prime candidate for a constituent of the dark matter in the universe. The Axion Resonant InterAction DetectioN Experiment (ARIADNE) is designed to search for axion-mediated spin-dependent interactions between nuclei at sub-millimeter ranges. The experiment involves a rotating non-magnetic mass to source the axion field, and a dense ensemble of laser-polarized He-3 nuclei to detect the axion field by Nuclear Magnetic Resonance. While participating in this research, a team of postdocs, graduate students, and undergraduate researchers will be broadly trained in the techniques of experimental atomic physics, optical pumping, nuclear magnetic resonance, low-temperature physics, micro-fabrication, magnetic shielding, vacuum systems, and modeling. This will be valuable preparation for work in basic or applied research, either in the U.S. or international work force or scientific community.The signal from an axion field can be resonantly enhanced by properly modulating the axion potential at the nuclear spin precession frequency. The goal of this award is to complete construction of the experiment, bring it through its commissioning phase during which possible systematics will be evaluated, and start the early data taking stage, exploring new parameter space for the PQ axion. The method has the potential to improve previous experimental and astrophysical bounds on axions by several orders of magnitude and probe deep into the theoretically interesting regime for the PQ axion. The experiment is also sensitive to more exotic axion-like particles. The new method can ultimately exceed present laboratory constraints on spin-dependent short-range forces by up to 8 orders of magnitude and can improve on the combined laboratory/astrophysical limits by a factor of 10^4 in the axion mass range of ma between 10 micro-eV and 10 milli-eV, probing deep into the traditional "PQ-axion window".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.