Collaborative Research: Novel Cavity Haloscopes for Axion Dark Matter at CM-Wavelengths

合作研究：CM 波长下轴子暗物质的新型腔光镜

• 批准号: 2209576
• 负责人: Chao-Lin Kuo
• 金额: $ 44.99万
• 依托单位: Stanford University
• 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 2025-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2209576&HistoricalAwards=false
• 关键词: Collaborative; Research; Novel; Cavity; Haloscopes

Astronomical observations have established that the Universe is primarily “dark” with approximately 85% of the matter made of yet unknown particles. Uncovering the nature of this dark matter will have far reaching consequences in cosmology, astrophysics and particle physics. The quantum chromodynamic (QCD) axion arises in an extension of the Standard Model of particle physics that would simultaneously solve the mystery of dark matter and the long-standing strong charge-parity problem. This award supports researchers at Stanford University and the University of Washington in the development of a novel axion detector called a haloscope that will improve the scan rate of axion dark matter experiments by more than three orders of magnitude at frequencies between 4 – 7 GHz. The awarded activities include outreach and education via a Summer Research Program for Teachers, and a mentorship program for graduate students in the training of undergraduate researchers. Above frequencies of approximately 4 GHz , corresponding to an axion particle mass of a few tens of micro-electronvolts, there exists a large sensitivity gap between current measurements and the theoretical benchmarks. Improving the scan rate at these frequencies is crucial to enhancing the reach of axion search experiments. The large gain of the new haloscope design is achieved by implementing a space-filling thin-shell cavity that decouples the resonator’s volume from its resonant frequency. A full-sized science-grade cavity will be fabricated and installed in an existing 250mK testbed to demonstrate tunability and high quality factor under cryogenic conditions. The cavities will also be integrated with a Josephson Junction-based amplifier and a digitizer to obtain new exclusion limits on searches for dark photons. These developments establish key preparations for future axion searches involving large-volume solenoid magnet systems like those currently utilized for the ADMX project.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.

天文观测已经确定，宇宙主要是“黑暗的”，大约85%的物质由未知粒子组成。 揭示这种暗物质的性质将在宇宙学，天体物理学和粒子物理学中产生深远的影响。 量子色动力学（QCD）轴子产生于粒子物理学标准模型的扩展，它将同时解决暗物质之谜和长期存在的强电荷宇称问题。 该奖项支持斯坦福大学和华盛顿大学的研究人员开发一种名为Haloscope的新型轴子探测器，该探测器将在4 - 7 GHz之间的频率下将轴子暗物质实验的扫描速率提高三个数量级以上。获奖活动包括通过教师暑期研究计划进行的推广和教育，以及为本科研究人员培训研究生的导师计划。以上的频率约为4 GHz，对应于一个轴子粒子质量的几十微电子伏特，存在一个大的灵敏度差距之间的电流测量和理论基准。 提高这些频率下的扫描速率对于增强轴子搜索实验的范围至关重要。 新的晕圈镜设计的大增益是通过实施空间填充薄壳腔来实现的，该腔使谐振器的体积与其谐振频率成比例。一个全尺寸的科学级腔体将被制造并安装在现有的250 mK测试平台上，以证明在低温条件下的可调谐性和高品质因数。 腔体还将与基于约瑟夫森结的放大器和数字化仪集成，以获得对暗光子搜索的新排除限制。 这些进展为未来的轴子研究做了重要的准备，这些研究涉及大容量螺线管磁体系统，如目前用于ADMX项目的系统。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进行评估，被认为值得支持。