Improved accuracy of the NPL-CsF2 primary frequency standard: evaluation of distributed cavity phase and microwave lensing frequency shifts

@article{Li2011ImprovedAO,
  title={Improved accuracy of the NPL-CsF2 primary frequency standard: evaluation of distributed cavity phase and microwave lensing frequency shifts},
  author={Ruoxin Li and K. Gibble and K. Szymaniec},
  journal={Metrologia},
  year={2011},
  volume={48},
  pages={283-289}
}
We evaluate the distributed cavity phase (DCP) and microwave lensing frequency shifts, which were the two largest sources of uncertainty for the NPL-CsF2 caesium fountain clock. We report measurements that confirm a detailed theoretical model of the microwave cavity fields and the frequency shifts of the clock that they produce. The model and measurements significantly reduce the DCP uncertainty to 1.1 ? 10?16. We derive the microwave lensing frequency shift for a cylindrical cavity with… Expand

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