Vacuum-Polarization Corrections to the Parity-Nonconserving6s−7sTransition Amplitude inC133s

The dominant one-loop radiative corrections to atomic wave functions, those associated with vacuum polarization in the nuclear Coulomb field, are evaluated for the $6s-7s$ parity-nonconserving transition amplitude in ${}^{133}\mathrm{Cs}$. These corrections increase the size of this amplitude by $0.4\%$ and, correspondingly, increase the difference between the experimental value of the weak charge $Q_W{(}^{133}\mathrm{Cs})$ and the value predicted by the standard model.