Design and construction of an apparatus for the experimental search for the electric dipole moment (EDM) of 129xe

129xe电偶极矩（EDM）实验搜索装置的设计与构建

• 批准号: 218861983
• 负责人: Professor Dr. Werner Heil
• 金额: --
• 依托单位: Institut für Physik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2012
• 资助国家: 德国
• 起止时间: 2011-12-31 至 2019-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/218861983?language=en
• 关键词: Design; construction; apparatus; experimental; search

We propose to measure the permanent electric dipole moment (EDM) of the isotope 129Xe, which would imply a breakdown of both parity P and time-reversal symmetry T and, through the CPT theorem, a breakdown in CP, the combined symmetries of charge conjugation C and parity P. Our goal is to improve the present experimental limit (dXe < 3x10-27 e cm) by about four orders of magnitude. Historically, the non-observation of EDMs of particles and atoms has ruled out more speculative models (beyond the Standard Model) than any other single experimental approach in particle physics. The most precise EDM limit was measured in the diamagnetic atom 199Hg (dHg < 3.1x10-29 e cm). To get more stringent limits, we propose a 3He/129Xe clock comparison experiment with the detection of free spin precession of gaseous, nuclear polarized 3He or 129Xe samples with a SQUID as magnetic flux detector. The precession of co-located 3He/129Xe nuclear spins can be used as ultra-sensitive probe for non-magnetic spin interactions of type Δν ~ dXeE, since the magnetic dipole interaction (Zeeman-term) drops out in the frequency difference Δν of their Larmor frequencies. Compared to spin masers, the detection of free spin precession with spin coherence times T > 1 day doesn’t have the systematic limitations of a feedback loop necessary to sustain coherent spin precession.

我们建议测量同位素 129Xe 的永久电偶极矩 (EDM)，这意味着宇称 P 和时间反转对称性 T 均被破坏，并且通过 CPT 定理，CP、电荷共轭 C 和宇称 P 的组合对称性也被破坏。我们的目标是将当前的实验极限 (dXe < 3x10-27 e cm) 提高约四个数量级。从历史上看，与粒子物理学中任何其他单一实验方法相比，对粒子和原子的 EDM 的非观察已经排除了更多的推测模型（超出标准模型）。最精确的 EDM 极限是在反磁性原子 199Hg (dHg < 3.1x10-29 e cm) 中测量的。为了获得更严格的限制，我们提出了 3He/129Xe 时钟比较实验，使用 SQUID 作为磁通量检测器来检测气态、核极化 3He 或 129Xe 样品的自由自旋进动。共位 3He/129Xe 核自旋的进动可用作 Δν ~ dXeE 型非磁自旋相互作用的超灵敏探针，因为磁偶极子相互作用（塞曼项）在其拉莫尔频率的频率差 Δν 中消失。与自旋脉泽相比，自旋相干时间 T > 1 天的自由自旋进动的检测不存在维持相干自旋进动所需的反馈回路的系统限制。

项目成果

Precise measurement of magnetic field gradients from free spin precession signals of 3He and 129Xe magnetometers

• DOI: 10.1140/epjd/e2017-70505-4
• 发表时间: 2016-08
• 期刊: The European Physical Journal D
• 作者: F. Allmendinger;P. Blümler;M. Doll;Olivier Grasdijk;W. Heil;K. Jungmann;S. Karpuk;H. Krause;A. Offenhäusser;M. Repetto;U. Schmidt;Y. Sobolev;K. Tullney;L. Willmann;S. Zimmer

HP-Xe to go: Storage and transportation of hyperpolarized (129)Xenon.

HP-Xe to go：超极化 (129) 氙气的储存和运输

• DOI: 10.1016/j.jmr.2016.02.011
• 发表时间: 2016
• 期刊: Journal of magnetic resonance
• 影响因子: 2.2
• 作者: M. Repetto;S. Zimmer;F. Allmendinger;P. Blümler;M. Doll;J.O. Grasdijk;W. Heil;K. Jungmann;S. Karpuk;H.-J. Krause;A. Offenhäusser;U. Schmidt;Y. Sobolev;L. Willmann
• 通讯作者: L. Willmann