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Creators/Authors contains: "Beattie, Scott"

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  1. ; ; ; ; (, Metrologia)
    Abstract We have made improvements in the stability, accuracy, and performance of the NRC-FCs2 fountain clock. The dominant systematic effects have been re-evaluated. Optically-stabilized microwaves are used to improve the short-term stability, now reaching $$\sigma_y = 3\;\times10^{-14}\;\tau^{-\frac{1}{2}}$$. We evaluate the distributed cavity phase shift using absorption imaging. This technique dramatically reduces the evaluation time and final uncertainty. We have re-evaluated biases due to microwave leakage and synchronous phase transients with higher accuracy. The total systematic uncertainty of NRC-FCs2 is now $$1.1 \times 10^{-16}$$ in fractional frequency, a factor of $$2$$ improvement over its most recent evaluation. 
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  2. ; ; ; ; ; ; ; (, Physical Review Letters)
    Free, publicly-accessible full text available December 1, 2025