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PUBLICATIONS

Long-term comparison of caesium fountain primary frequency standards

Published

Author(s)

Thomas E. Parker

Abstract

There are currently nine caesium fountain primary frequency standards regularly reporting calibrations of International Atomic Time to the Bureau International des Poids et Measures (BIPM). An investigation has been carried out using data from the BIPM publication Circular T to evaluate the frequency differences among these standards and to determine whether these offsets are consistent with the stated uncertainties. The results of this investigation show that the standards agree well with each other. An overall estimate of the caesium frequency is made using the weighted mean of all the fountains.
Citation
Metrologia
Volume
47
Pub Type
Journals

Download Paper

Local Download

Keywords

atomic, caesium, fountain, frequency, standard
Physics and Standards

Citation

Parker, T. (2009), Long-term comparison of caesium fountain primary frequency standards, Metrologia, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=903472 (Accessed October 11, 2025)

Issues

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Created December 7, 2009, Updated February 19, 2017
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