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Invited Review Article: The uncertainty in the realization and dissemination of the SI second from a systems point of view

Published

Author(s)

Thomas E. Parker

Abstract

The uncertainty in the realization and dissemination of the SI second is determined by the characteristics of three major components: (1) the primary frequency standards themselves, (2) the time scale fly wheels that provide a continuously present frequency reference, and (3) the frequency transfer systems. Currently these three systems contribute at approximately equal levels at the mid 10-16 range over 20 to 30 days of averaging time to the practical delivery of the SI second to the most demanding users. Any significant improvement in one system requires similar improvements in the other two systems in order for users to see the full benefits.
Citation
Review of Scientific Instruments
Volume
83

Keywords

atomic frequency standards, time scales, time and frequency transfer

Citation

Parker, T. (2012), Invited Review Article: The uncertainty in the realization and dissemination of the SI second from a systems point of view, Review of Scientific Instruments (Accessed April 15, 2024)
Created February 23, 2012, Updated February 19, 2017