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arXiv · 1508.05996

Intermittent optical frequency measurements to reduce the dead time uncertainty of frequency link

Hidekazu Hachisu·Tetsuya Ido
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Abstract

The absolute frequency of the $^{87}{\rm Sr}$ lattice clock transition was evaluated with an uncertainty of $1.1\times 10^{-15}$ using a frequency link to the international atomic time (TAI). The frequency uncertainty of a hydrogen maser used as a transfer oscillator was reduced by homogeneously distributed intermittent measurement over a five-day grid of TAI. Three sets of four or five days measurements as well as systematic uncertainty of the clock at $8.6\times 10^{-17}$ have resulted in an absolute frequency of $^{87}{\rm Sr}\ {}^1S_0 - {}^3P_0$ clock transition to be 429 228 004 229 872.85 (47) Hz.

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Hidekazu Hachisu, Tetsuya Ido. 2015-08-24. Intermittent optical frequency measurements to reduce the dead time uncertainty of frequency link. https://doi.org/10.7567/jjap.54.112401

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