In this paper, we present some results of shell-model calculations employing effective interactions derived from the CD-Bonn free nucleon-nucleon potential. These concern 18O, 134Te, and 210Po, and are part of a comprehensive study of nuclei around doubly closed shells. Comparison of the calculated results with experimental data illustrates the degree of accuracy of modern realistic shell-model...

The second quantized form of Rayleigh-Schrodinger perturbation theory is symbolically manipulated to derive many-body perturbation theory (MBPT) formulas for particle-hole excited states of closed shell atoms. The analytic results obtained from the symbolic code, written in Mathematica, will be presented for the lowest orders of MBPT. These results compare exactly with the results obtained by h...

Excitation energies for 3l-4l8 particle-hole states of Ni-like ions are determined to second order in relativistic many body perturbation theory. The calculations start from a closed-shell Dirac-Fock potential, and include second-order Coulomb and Breit-Coulomb interactions. Retarded electric-dipole matrix elements ~in length and velocity forms! are calculated in second order for transitions fr...

The two-body momentum distribution η 2 (p 1 , p 2) of nuclei is studied. First, a compact analytical expression is derived for Z = N , ℓ-closed nuclei, within the context of the independent particle shell model. Application to the light closed-shell nucleus 16 O is included and discussed. Next, the effect of dynamical, short-range correlations is investigated in the case of the light nucleus 4 ...

We develop a shell-model Monte Carlo (SMMC) method to calculate densities of states with varying exciton (particle-hole) number. We then apply this method to the doubly closed-shell nucleus 40 Ca in a full 0s-1d-0f-1p shell-model space and compare our results to those found using approximate analytic expressions for the partial densities. We find that the effective one-body level density is red...

Shannon information entropies in position and momentum spaces and their sum are calculated as functions of Z(2 < or = Z < or = 54) in atoms. Roothaan-Hartree-Fock electron wave functions are used. The universal property S = a + b ln Z is verified. In addition, we calculate the Kullback-Leibler relative entropy, the Jensen-Shannon divergence, Onicescu's information energy, and a complexity measu...

We consider the proton and neutron quasiparticle orbits around the closed-shell (56)Ni and (48)Ca isotopes. It is found that large model spaces (beyond the capability of shell model applications) are necessary for predicting the quenching of spectroscopic factors. The particle-vibration coupling is identified as the principal mechanism. Additional correlations--due to configuration with several...

We develop a shell-model Monte Carlo method to calculate densities of states with varying exciton ~particlehole! number. We then apply this method to the doubly closed-shell nucleus Ca in a full 0s-1d-0 f -1p shell-model space and compare our results to those found using approximate analytic expressions for the partial densities. We find that the effective one-body level density is reduced by a...

We present a new and efficient method to obtain a Gamow shell-model basis and matrix elements generated by realistic nucleon-nucleon interactions. We derive a self-consistent Hartree-Fock potential from the renormalized NLO interaction model. The corresponding Gamow one-body eigenstates are generated in a plane wave basis in order to build a Gamow shell-model set of basis states for the closed ...

We calculate electromagnetic form factors of the proton bound in specified orbits for several closed shell nuclei. The quark structure of the nucleon and the shell structure of the finite nuclei are given by the QMC model. We find that orbital electromagnetic form factors of the bound nucleon deviate significantly from those of the free nucleon.