激光冷却铯原子喷泉频标的黑体辐射频移

研究了激光冷却铯原子喷泉频标的黑体辐射频移（包括黑体辐射塞曼频移和黑体辐射斯塔克频移），推导了频移的计算公式，估算了室温下频移及其不确定度的大小，分析了黑体辐射频移对频标准确度的影响。结果表明：１）室温下黑体辐射塞曼频移可达１０＾－１５量级，在评定铯原子喷泉频标准确度时，需要对此项频移加以修正；２）在利用直流斯塔克效应估算黑体辐射斯塔克频移时，由直流极化率常数ｘ的测量误差导致的黑体辐射斯塔克频移的

Frequency Shift Due to Blackbody Radiation in the Laser-Cooled Cesium Fountain Frequency Standard

The shift of the cesium hyperfine transition frequency due to blackbody radiation is investigated. The formulas for calculating the shift are derived, and the shift as well as the uncertainty at room temperature is evaluated. In addition, the effect of the frequency shift due to blackbody radiation on the accuracy of the laser-cooled cesium fountain frequency standard is analyzed. Blackbody ac Zeeman shift at room temperature is calculated to be of 10-15 order, thus should be corrected for the cesium fountain frequency standard in determining the accuracy of the standard. When the blackbody ac Stark shift of cesium hyperfine transition is evaluated by determining the dc Stark effect, the uncertainty in the determination of 133Cs dc hyperfine polarizability constant κ will bring out a fractional frequency uncertainty of about 4×10-16 to the correction of blackbody ac Stark shift. This uncertainty is one of the critical factors governing the accuracy level of the cesium fountain frequency standard. In this connection, more precise experiments to determine 133Cs dc hyperfine Stark shift are desirable.