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Improvements in NIST-F1 and a Resulting Accuracy of δf/f = 0.61 × 10-15

Published

Author(s)

Thomas P. Heavner, Steven R. Jefferts, Elizabeth A. Donley, Jon H. Shirley, Thomas E. Parker

Abstract

Over the last several years we have made many improvements to NIST-F1 (a laser-cooled cesium fountain primary frequency standard) resulting in a reduction in the uncertainty by nearly a factor of 2 in the realization of the SI second at NIST. We recently submitted an evaluation with a combined standard fractional uncertainty of 0.61 × 10-15 to the BIPM (Bureau International des Poids et Mesures). The total fractional uncertainty of the evaluation (including dead time and time transfer contributions) was 0.88 × 10-15. This is the smallest uncertainty in a frequency standard yet submitted to the BIPM.
Proceedings Title
Proc. IEEE Intl. Ultrasonics, Ferroelectrics, and Frequency Control Anniversary Joint Conf.
Conference Dates
August 24-27, 2004
Conference Location
Montreal, CA
Conference Title
IEEE Intl. Ultrasonics, Ferroelectrics, and Frequency Control Conf.

Keywords

ces, gen, time

Citation

Heavner, T. , Jefferts, S. , Donley, E. , Shirley, J. and Parker, T. (2004), Improvements in NIST-F1 and a Resulting Accuracy of &#948;f/f = 0.61 &#215; 10<sup>-15</sup>, Proc. IEEE Intl. Ultrasonics, Ferroelectrics, and Frequency Control Anniversary Joint Conf., Montreal, CA, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=50084 (Accessed June 23, 2024)

Issues

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Created August 23, 2004, Updated February 17, 2017