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-4的佩宁陷质量测量

S Sasidharan^1,2,3, O Bezrodnova¹, S Rau¹

¹Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany.

Physical review letters

|September 18, 2023

概括

研究人员使用LIONTRAP设施精确测量了-4的原子质量. 这种新的,高度准确的-4的质量值与当前的文献值有很大差异.

科学领域:

原子物理原子物理
计量学计量学计量学
核物理核物理核物理

背景情况:

精确的原子质量测量对于测试物理理论和建立基本常数至关重要.
之前对-4原子质量的测量已经达到很高的精度,但可能存在差异.

研究的目的:

以前所未有的精度确定-4 ($^{4}$He) 的原子质量.
为$^{4}$He原子质量提供一个独立的,高精度的值,以与现有数据和理论预测进行比较.

主要方法:

使用光离子陷 (LIONTRAP) 装置,这是一个高精度的Penning-trap质谱仪.
测量了 $^{4}$He$^{2+}$ 离子的质量,精确度为每万亿分之12的部分.
从离子质量测量计算中性 $ ^ {4} $ He 原子质量.

主要成果:

报告了对$^{4}$He$^{2+}$离子质量的测量:m($^{4}$He$^{2+}$) =4.001506179651(48) u.
确定中性 $^{4}$He 的原子质量: m($^{4}$He) =4.002603254653(48) u.
新的测量比CODATA18值稍微准确一些.

结论:

确定 $^{4}$He 的原子质量与 CODATA18 的值偏离了 6.6 个标准偏差.
这种显著的偏差需要进一步调查,可能表明需要重新评估当前的原子质量数据或理论模型.
取得的高精度凸显了LIONTRAP设备对于基本常数测量的能力.

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