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Time and Frequency Technology Related to the Operation of a Cesium Fountain Primary Frequency Standard



Thomas E. Parker


The operation of a cesium fountain primary frequency standard is greatly facilitated by the presence of two other important capabilities. The first is a stable frequency reference and the second is one or more high stability frequency transfer systems. A stable frequency reference such as a hydrogen maser is virtually a necessity since absolutely no fountain dead time can be tolerated without it. Also, some systematic biases in the fountain become very difficult to evaluate without a stable reference. State-of-the-art frequency transfer technology also is necessary if the fountain is intended to contribute to TAI, or to be compared to other remote frequency standards without excessive degradation of stated uncertainties. This paper discusses the facilities available at the National Institute of Standards and Technology (NIST) and how they impact the operation of NIST-FI, the primary frequency standard at NIST.
Proceedings Title
Proceedings| ATF2004
Conference Dates
October 1, 2004
Conference Location
Beijing, CH
Conference Title


cesium fountain, frequency transfer, primary frequency standard, time transfer


Parker, T. (2004), Time and Frequency Technology Related to the Operation of a Cesium Fountain Primary Frequency Standard, Proceedings| ATF2004, Beijing, CH, [online], (Accessed May 29, 2024)


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Created October 1, 2004, Updated February 17, 2017