在接近零磁场下,改进了基基态超细结构的测量
P Strasser1,2,3, S Fukumura4, R Iwai1
1Muon Science Laboratory, Institute of Materials Structure Science (IMSS), High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan.
Physical review letters
|January 5, 2024
概括
对原子超细结构 (HFS) 的新测量为基本常数提供了更精确的值. 这项研究推进了我们对原子物理学的理解,并测试了量子电力学理论.
科学领域:
- 原子物理 原子物理
- 量子电动力学 量子电动力学
- 基本常数 基本常数
背景情况:
- 原子超细结构 (HFS) 的测量对于测试三体原子系统和边界状态量子电动力学至关重要.
- 这些测量还确定了基本常数,包括负的磁矩和质量.
- 通过比较阳性和阴性子测试,测试CPT不变性.
研究的目的:
- 在接近零磁场下,对基-4原子进行新的地面状态HFS测量.
- 为了提高以前测量的精度,并测试CPT不变性.
- 为了研究和的频率转移对同位素的影响.
主要方法:
- 在日本质子加速器研究综合体 (J-PARC) 的子科学设施 (MuSAIF) 使用了世界上最强的脉冲负束.
- 采用小量的CH4作为电子捐赠体,以有效地形成中性原子.
- 在接近零的磁场和条件下进行测量,以研究密度依赖的频率转移.
主要成果:
- 实现了新的,更精确的离子-4的地面状态HFS测量:Δν=4464.980(20) MHz (4.5 ppm).
- 这一结果超过了以前在弱磁场和高磁场下进行的所有测量的精度.
- 在目前的实验精度内,没有观察到和的同位素效应.
结论:
- 新的HFS对-4的测量显著提高了精度,有助于量子电动力学测试和基本常数的确定.
- 这项研究证明了J-PARC MuSAIF设施对先进的原子物理研究的能力.
- 没有观察到的同位素效应为了解原子及其相互作用提供了有价值的数据.
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