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arXiv · hep-ph/0005274

Reconciliation of the Measurement of Parity-Nonconservation in Cs with the Standard Model

Abstract

Contributions from the Breit interaction in atomic-structure calculations account for 1.3sigma of the previously reported 2.5sigma deviation from the Standard Model in the 133Cs weak charge [S.C. Bennett and C.E. Wieman, Phys. Rev. Lett. 82, 2484 (1999)]. The updated corrections for the neutron distribution reduce the discrepancy further to 1.0sigma. The updated value of the weak charge is Q_W(133Cs) = -72.65(28)_{expt}(34)_{theor}. The present analysis is a higher-order extension of previous calculation [A. Derevianko, E-print physics/0001046].

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A. Derevianko. 2000-08-02. Reconciliation of the Measurement of Parity-Nonconservation in Cs with the Standard Model. https://doi.org/10.1103/physrevlett.85.1618

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