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Cancellation of the collisional frequency shift in caesium fountain clocks

K. Szymaniec·W. Chalupczak·E. Tiesinga·C. J. Williams·S. Weyers·R. Wynands
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Abstract

We have observed that the collisional frequency shift in primary caesium fountain clocks varies with the clock state population composition and, in particular, is zero for a given fraction of the |F = 4, mF = 0> atoms, depending on the initial cloud parameters. We present a theoretical model explaining our observations. The possibility of the collisional shift cancellation implies an improvement in the performance of caesium fountain standards and a simplification in their operation. Our results also have implications for test operation of fountains at multiple pi/2 pulse areas.

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K. Szymaniec, W. Chalupczak, E. Tiesinga, C. J. Williams, S. Weyers, R. Wynands. 2006-12-12. Cancellation of the collisional frequency shift in caesium fountain clocks. https://doi.org/10.1117/12.732017

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