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Updated: May 4, 2026

Implementation of a Reference Interferometer for Nanodetection
Published on: April 26, 2014
An evaluation of the frequency shift caused by collisions with background gas in the primary frequency standard
Abstract:
Collisions between cold cesium atoms and background gas atoms at ambient temperature reduce the cold atom signal in a fountain clock and at the same time produce a shift in the measured clock frequency. We evaluate the shift in the NPL-CsF2 cesium fountain primary frequency standard based on measurements of the fractional loss of cold atoms from the atomic cloud during the interrogation time combined with a model by Gibble that quantifies the relationship between the loss and the frequency shift.
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