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arXiv · 1211.5565

Direct Observation of Resonant Scattering Phase Shifts and their Energy Dependence

Stephen D. Gensemer·Ross B. Martin-Wells·Aaron W. Bennett·Kurt Gibble
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Abstract

We scan the collision energy of two clouds of cesium atoms between 12 and 50 $\mu$K in atomic fountain clock. By directly detecting the difference of s-wave scattering phase shifts, we observe a rapid variation of a scattering phase shift through a series of Feshbach resonances. At the energies we use, resonances that overlap at threshold become resolved. Our statistical phase uncertainty of 8 mrad can be improved in future precision measurements of Feshbach resonances to accurately determine the Cs-Cs interactions, which may provide stringent limits on the time variation of fundamental constants.

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Stephen D. Gensemer, Ross B. Martin-Wells, Aaron W. Bennett, Kurt Gibble. 2012-11-23. Direct Observation of Resonant Scattering Phase Shifts and their Energy Dependence. https://doi.org/10.1103/physrevlett.109.263201

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