从基于频率的测量中获得的分子线强度比率的前所未有的准确性
Jin-Ke Li1,2, Jin Wang1, Rui-Heng Yin3
1Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, China.
Science advances
|September 17, 2025
概括
精确的分子物理测量现在可以达到0.003%的过渡强度准确度. 这种新方法重新定义了光学气体温度计,使得高精度的国际单位系统可追溯测量.
科学领域:
- 量子化学是一种量子化学.
- 光学气体计量学 在光学气体计量学
- 分子光谱学 分子光谱学
背景情况:
- 精确的分子过渡强度对于量子化学和计量学至关重要.
- 从历史上看,对简单的二原子分子的准确性仅限于0.1%.
研究的目的:
- 开发一种更准确的方法来确定分子过渡强度.
- 为了提高光学气体温度计的精度.
主要方法:
- 使用了相对强度比的频域测量.
- 采用双波长腔模式分散光谱学.
- 杆式高精度频率计量学.
主要成果:
- 在分子过渡强度测量中达到0.003%的准确性.
- 揭示了与最先进的初始计算的差异.
- 用线强度比温度计 (LRT) 确定气体温度,具有0.5毫克尔文的统计不确定性.
结论:
- 频域强度比率测量显著超过绝对方法.
- 该技术重新定义了光学气体计量学的极限.
- 建立强度比作为精确分子物理学和国际单位系统可追溯测量的范式.
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