Axion Dark Matter eXperiment at High Frequency (ADMX-HF)

现在，所有的天体物理学和宇宙学数据都令人信服地指向宇宙中冷暗物质（CDM）的一个很大组成部分，而光轴子是一个很好的候选者。人们早就知道，如果轴子是我们银河系晕的暗物质的主要组成部分，那么它们可以通过由磁场渗透的微波腔谐振器组成的装置转换成窄带微波信号而被探测到。自1996年以来，轴子暗物质实验（ADMX）一直在寻找轴子，在轴子模型的波段内获得了很好的灵敏度，排除了几个微ev范围内的质量。随着最近的技术进步，现在可以将这些测量扩展到更高的频率。该合同将使耶鲁大学团队能够加入ADMX合作，并建立和操作第二个微波腔实验，即ADMX at High frequency (ADMX- hf)，探测2-20 GHz（~8至80微ev）范围。这个括号括住了轴子的质量，对应于宇宙物质密度的饱和（~ 20微电子伏特）。因此，作为“一个实验，两个地点”的ADMX将能够采取双管齐下的策略，同时推动轴-光子耦合的向下和质量的向上。在更广泛的影响中，ADMX已经被证明是前沿技术的驱动者；十多年前，NSF支持为ADMX开发近量子限制的SQUID放大器，该放大器迅速分离出来，成为IARPA（智能高级研究项目活动）量子计算路线图的关键部分。ADMX-HF同样可以从耶鲁大学深厚的量子电子学能力中汲取经验，提供有利于基础科学和安全的新创新。长期以来，PI一直雇佣本科生从事他的研究工作。

All astrophysical and cosmological data now point convincingly to a large component of Cold Dark Matter (CDM) in the Universe, for which a light axion is a well-motivated candidate. It has long been known that if axions are a primary constituent of the dark matter of our own Milky Way halo, they may be detected through their conversion into a narrow-band microwave signal by an apparatus consisting of a microwave-cavity resonator permeated by a magnetic field. Since 1996, the Axion Dark Matter eXperiment (ADMX) has been searching for axions, achieving sensitivities well within the band of axion models, excluding masses in the few micro-eV range. With recent technological advances, it is now possible to extend these measurements to higher frequencies. This award will enable the Yale group to join the ADMX collaboration and to build and operate a second microwave cavity experiment, ADMX at High Frequencies (ADMX-HF), to probe the 2-20 GHz (~8 to 80 micro-eV) range. This brackets the mass of the axion which corresponds to saturation of the matter density of the universe (~ 20 micro-eV). ADMX as "one experiment, two sites" will thus be able to pursue a two-prong strategy, simultaneously pushing downwards in the axion-photon coupling and upwards in mass.In Broader Impacts, ADMX has already proven to be a driver of leading-edge technology; NSF supported the development of the near-quantum limited SQUID amplifiers for ADMX more than a decade ago, which quickly spun off to become a critical piece of IARPA's (Intelligence Advanced Research Projects Activity) roadmap in quantum computing. ADMX-HF can similarly be expected to draw from the deep quantum electronics competency at Yale to provide new innovations benefiting basic science and security. The PI has a long history of employing undergraduates to work on his research.