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Determination of the scalar and vector polarizabilities of the cesium $6s ^2S_{1/2} rightarrow 7s ^2S_{1/2}$ transition and implications for atomic parity non-conservation

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 نشر من قبل George Toh
 تاريخ النشر 2019
  مجال البحث فيزياء
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Using recent high-precision measurements of electric dipole matrix elements of atomic cesium, we make an improved determination of the scalar ($alpha$) and vector ($beta$) polarizabilities of the cesium $6s ^2S_{1/2} rightarrow 7s ^2S_{1/2} $ transition calculated through a sum-over-states method. We report values of $alpha = -268.82 (30) a_0^3$ and $beta = 27.139 (42) a_0^3$ with the highest precision to date. We find a discrepancy between our value of $beta$ and the past preferred value, resulting in a significant shift in the value of the weak charge $Q_w$ of the cesium nucleus. Future work to resolve the differences in the polarizability will be critical for interpretation of parity non-conservation measurements in cesium, which have implications for physics beyond the Standard Model.



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