The Coulomb sum rule is studied using the random-phase approximation to the relativistic σωρ model. The addition of the ρ meson to the σω model has a large effect on the quenching of the sum rule because of its random-phase approximation correlation and its coupling with the isovector anomalous magnetic moment of the nucleon. The low-density surfaces of finite nuclei have a larger response than their interior so that the quenching of the Coulomb sum rule is not as significant as in the nuclear matter ground state. Calculations for finite nuclei using the local density approximation agree with existing experimental data on ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$, ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$, ${}_{}{}^{48}{}_{}{}^{}\mathrm{Ca}$, and ${}_{}{}^{56}{}_{}{}^{}\mathrm{Fe}$.

• Received 14 November 1988

DOI:https://doi.org/10.1103/PhysRevC.39.1668