Some higher-order corrections to renormalized Brueckner-Hartree-Fock calculations are estimated for the nuclei ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$, ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$, and ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$. The diagrams of interest are the potential insertions in particle lines and the two-body correlation corrections to the rms radii. Studies are made of the sensitivity of these corrections to the shift in the intermediate spectrum used to calculate the $G$ matrix. The correlation corrections to the radii are small and seem to increase somewhat as the intermediate spectrum is lowered, but there is no appreciable change in the over-all saturation properties. The errors involved in estimating the corrections are discussed. "Off-diagonal occupation probabilities" are also calculated and found to be small, thereby justifying ignoring such diagrams as is usually done in renormalized Brueckner calculations.

• Received 7 November 1972

DOI:https://doi.org/10.1103/PhysRevC.7.943