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Comparing Room Temperature and Cryogenic Cesium Fountains



Steven R. Jefferts, Thomas P. Heavner, Thomas E. Parker, Jon H. Shirley, Elizabeth A. Donley, Filippo Levi, Davide Calonico, C Calosso, Giovanni Costanzo, B. Mongino


We have compared the frequency of a room temperature cesium fountain primary frequency standard with that of a cryogenic (~80K) cesium fountain. This comparison yields a measurement of the blackbody frequency shift of the room temperature fountain.
Proceedings Title
Proceedings of the 2011 Joint IEEE International Frequency Control Symposium and European Frequency and Time Forum
Conference Dates
May 1-5, 2011
Conference Location
San Francisco, CA


Blackbody Radiation Shift, Cesium Fountain, Primary Frequency Standard
Created July 31, 2011, Updated February 19, 2017