Precise calculation of parity nonconservation in cesium and test of the standard model
نویسندگان
چکیده
We have calculated the 6s − 7s parity nonconserving (PNC) E1 transition amplitude, E P N C , in cesium. We have used an improved all-order technique in the calculation of the correlations and have included all significant contributions to E P N C. Our final value E P N C = 0.904 1 ± 0.5% × 10 −11 iea B (−Q W /N) has half the uncertainty claimed in old calculations used for the interpretation of Cs PNC experiments. The resulting nuclear weak charge Q W for Cs deviates by about 2σ from the value predicted by the standard model.
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