NIM6铯喷泉钟背景气体碰撞频移的评估  

Evaluation of the Background Gas Collision Frequency Shift in NIM6 Cesium Fountain Clock

作　　者：陈伟亮[1] 房芳[1] 袁小迪 韩蕾 刘昆[1] 戴少阳 刘年丰[1] 李天初[1] CHENG Weiliang;FANG Fang;YUAN Xiaodi;HAN Lei;LIU Kun;DAI Shaoyang;LIU Nianfeng;LI Tianchu(National Institute of Metrology of China,Beijing 100029,China;Beijing Institute of Technology,Beijing 100082,China)

机构地区：[1]中国计量科学研究院,北京100029 [2]北京理工大学,北京100081

出　　处：《计量技术》2020年第5期11-13,6,共4页Measurement Technique

摘　　要：当铯喷泉钟的频率不确定度进入10-16量级时,需要考虑背景气体碰撞频移的不确定度贡献。在传统理论模型的基础上,结合NIM6铯喷泉钟的设计参数,计算和比较了上升段和下落段探测原子损耗与微波腔截止波导引入的原子损耗,提出对背景气体碰撞引发原子数损失的修正计算方法,给出NIM6铯喷泉钟背景气体碰撞频移不确定度为2.0×10-17。When the frequency uncertainty of a cesium fountain clock reaches 10-16,the contribution of the uncertainty of the background gas collision frequency shift needs to be considered. Based on the traditional theoretical model and the design parameters of NIM6 cesium fountain clock,the atomic losses detected between the rising and falling phase and those introduced by the microwave cavity cut-off waveguide were calculated and compared. A modified method to calculate atomic loss induced by background gas collision was proposed,and the related uncertainty of the frequency shift of the background gas collision of the NIM6 cesium fountain clock is 2. 0 × 10-17.

关 键 词：铯喷泉钟 碰撞频移 背景气体 不确定度 

分 类 号：TH714.14[机械工程—测试计量技术及仪器]