Astroparticle Physics with a Trapped Electron

俘获电子的天体粒子物理学

• 批准号: EP/Y036263/1
• 负责人: Jack Devlin
• 金额: $ 269.44万
• 依托单位: Imperial College London
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2024
• 资助国家: 英国
• 起止时间: 2024 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FY036263%2F1
• 关键词: Astroparticle; Physics; Trapped; Electron

No one knows what 84% of the matter in the universe is, and the goal of APTE is tofind out. APTE will investigate two leading types of dark matter: axions and millichargedparticles. Axions not only resolve a longstanding puzzle in particle physics, but if theirmass is 0.001-1 meV they are an excellent dark matter candidate. Millicharged particlesarise in some theories beyond the Standard Model and have recently been suggested as a com-ponent of dark matter that could explain the anomalous cooling of hydrogen in the early universe.APTE will use an electron in a cryogenic Penning trap in an entirely new application: aquantum sensor for astroparticle physics. The radial modes of the trapped electron will bemonitored for transitions caused by collisions with millicharged dark matter or the absorptionof single microwave photons from axion decays. Changes in radial quantum state will beimprinted onto the trapped electron's axial frequency using a strong magnetic inhomogeneity,the same principle as used to measure the electron magnetic moment. Drawing on myexperience in BASE, one of the world's most sensitive cryogenic Penning traps, I will pioneerthe use of advanced phase sensitive measurement protocols of my own invention. These willbe used to monitor the electron's axial frequency for phase jumps which occur when the radialmode changes. With this electron single photon counter we will be able to overcome the Stan-dard Quantum Limit which severely degrades our ability to investigate axion masses > 0.04 meV.APTE will perform a first search for dark matter axions with masses around 0.128 meVand millicharged dark matter particles with masses up to at least 1 GeV and charges 10^-1 to 10^-7 e. Both measurements probe important theories in a regime where there is currently nodata and few proposed experiments. This ground-breaking project will lay the foundations fora future program of axion searches, as well as other applications in fundamental physics.

没有人知道宇宙中 84% 的物质是什么，APTE 的目标就是找出答案。 APTE 将研究暗物质的两种主要类型：轴子和毫带电粒子。轴子不仅解决了粒子物理学中长期存在的难题，而且如果它们的质量为 0.001-1 meV，它们就是极好的暗物质候选者。毫带电粒子出现在标准模型之外的一些理论中，最近被认为是暗物质的一个组成部分，可以解释早期宇宙中氢的异常冷却。APTE 将在一个全新的应用中使用低温潘宁陷阱中的电子：用于天体粒子物理学的量子传感器。被捕获电子的径向模式将被监测，以发现由与毫荷暗物质碰撞或轴子衰变吸收单个微波光子引起的跃迁。利用强磁不均匀性，径向量子态的变化将被印在被捕获电子的轴向频率上，这与测量电子磁矩的原理相同。凭借我在 BASE（世界上最灵敏的低温潘宁陷阱之一）的经验，我将率先使用我自己发明的先进相敏测量协议。这些将用于监测电子的轴向频率，以防止径向模式变化时发生的相位跳跃。有了这个电子单光子计数器，我们将能够克服标准量子极限，这严重降低了我们研究轴子质量 > 0.04 meV 的能力。APTE 将首次搜索质量约为 0.128 meV 的暗物质轴子和毫带电暗物质粒子质量至少高达 1 GeV，电荷为 10^-1 至 10^-7 e。这两项测量都在目前没有数据且很少提出实验的情况下探讨了重要的理论。这个突破性的项目将为未来的轴子搜索计划以及基础物理学的其他应用奠定基础。