Department of Physics, 366 Le Conte Hall MC 7300, University of California, Berkeley, CA 94720, USA.
Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, CA 94720, USA.
Science. 2018 Apr 13;360(6385):191-195. doi: 10.1126/science.aap7706. Epub 2018 Apr 12.
Measurements of the fine-structure constant α require methods from across subfields and are thus powerful tests of the consistency of theory and experiment in physics. Using the recoil frequency of cesium-133 atoms in a matter-wave interferometer, we recorded the most accurate measurement of the fine-structure constant to date: α = 1/137.035999046(27) at 2.0 × 10 accuracy. Using multiphoton interactions (Bragg diffraction and Bloch oscillations), we demonstrate the largest phase (12 million radians) of any Ramsey-Bordé interferometer and control systematic effects at a level of 0.12 part per billion. Comparison with Penning trap measurements of the electron gyromagnetic anomaly - 2 via the Standard Model of particle physics is now limited by the uncertainty in - 2; a 2.5σ tension rejects dark photons as the reason for the unexplained part of the muon's magnetic moment at a 99% confidence level. Implications for dark-sector candidates and electron substructure may be a sign of physics beyond the Standard Model that warrants further investigation.
测量精细结构常数α需要来自各个子领域的方法，因此是检验物理理论和实验一致性的有力手段。我们利用物质波干涉仪中铯-133 原子的反冲频率，记录了迄今为止最精确的精细结构常数测量值：α=1/137.035999046(27)，精度达到 2.0×10。我们利用多光子相互作用（布拉格衍射和布洛赫振荡），展示了任何拉姆齐-博尔德干涉仪中最大的相位（1200 万弧度），并将系统效应控制在十亿分之 0.12 的水平。与通过粒子物理标准模型对电子回旋磁比率-2 的彭宁阱测量相比，现在受到-2不确定性的限制；在 99%置信水平下，2.5σ 张力拒绝暗光子是未解释的μ子磁矩部分的原因。这对于暗物质候选物和电子亚结构可能是超出标准模型的物理的一个迹象，值得进一步研究。
