# Improved Frequency Measurement of the 1 S 0 - 3 P 0 Clock Transition in 87 Sr Using a Cs Fountain Clock as a Transfer Oscillator

@article{Tanabe2015ImprovedFM, title={Improved Frequency Measurement of the 1 S 0 - 3 P 0 Clock Transition in 87 Sr Using a Cs Fountain Clock as a Transfer Oscillator}, author={Takehiko Tanabe and Daisuke Akamatsu and Takumi Kobayashi and Akifumi Takamizawa and Shinya Yanagimachi and Takeshi Ikegami and Tomonari Suzuyama and Hajime Inaba and Sho Okubo and Masami Yasuda and Feng-Lei Hong and Atsushi Onae and Kazumoto Hosaka}, journal={Journal of the Physical Society of Japan}, year={2015}, volume={84}, pages={115002} }

We performed an absolute frequency measurement of the 1S0–3P0 transition in 87Sr with a fractional uncertainty of 1.2 × 10−15, which is less than one-third that of our previous measurement. A caesium fountain atomic clock was used as a transfer oscillator to reduce the uncertainty of the link between a strontium optical lattice clock and the SI second. The absolute value of the transition frequency is 429 228 004 229 873.56(49) Hz.

## 25 Citations

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