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Cancellation of the collisional frequency shift in caesium fountain clocks
K Szymaniec1, W Chałupczak, E Tiesinga
1National Physical Laboratory, Hampton Road, Teddington, TW11 0LW, United Kingdom.
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.
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