two-body Euler equations provide correlation functions variationally more effective than those obtained with the same technique in infinite nuclear matter.

We study the ground state properties of doubly closed shell nuclei 16 O and

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The ground state properties of N=Z, doubly closed shell nuclei are studied within Correlated Basis Function theory. A truncated version of the Urbana v 14 realistic potential, with spin, isospin and tensor components, is adopted, together with state dependent correlations. Fermi Hypernetted Chain integral equations are used to evaluate density, distribution function and ground state energy of 16 O and 40 Ca. The nuclear matter Single Operator Chain approximation is extended to finite nuclear systems, to deal with the non commuting part of the correlation operators. The results favourably compare with the variational Monte Carlo estimates, when available, and provide a first substantial check of the accuracy of the cluster summation method for state dependent correlations. We achieve in finite nuclei a treatment of non central interactions and correlations having, at least, the same level of accuracy as in nuclear matter. This opens the way for a microscopic study of 1

The proton momentum and density distributions of closed shell nuclei are calculated with a model treating short-range correlations up to first order in the cluster expansion. The validity of the model is verified by comparing the results obtained using purely scalar correlations with those produced by finite nuclei Fermi hypernetted chain calculations. State dependent correlations are used to calculate momentum and density distributions of 12 C, 16 O, 40 Ca, and 48 Ca, and the effects of their tensor components are studied.

The momentum distributions, natural orbits, spectroscopic factors and quasi-hole wave functions of the 12 C , 16 O , 40 Ca , 48 Ca , and 208 Pb doubly closed shell nuclei, have been calculated in the framework of the Correlated Basis Function theory, by using the Fermi hypernetted chain resummation techniques. The calculations have been done by using the realistic Argonne v ′ 8 nucleon-nucleon potential, together with the Urbana IX three-body interaction. Operator dependent correlations, which consider channels up to the tensor ones, have been used. We found noticeable effects produced by the correlations. For high momentum values, the momentum distributions show large enhancements with respect to the independent particle model results. Natural orbits occupation numbers are depleted by about the 10% with respect to the independent particle model values. The effects of the correlations on the spectroscopic factors are larger on the more deeply bound states.

We study the properties of hypernuclei containing one Λ hyperon in the framework of the correlated basis function theory with Jastrow correlations. Fermi hypernetted chain integral equations are derived and used to evaluate energies and one-body densities of Λ-hypernuclei having a doubly closed shell nucleonic core in the jj coupling scheme, from Carbon to Lead. We also study hypernuclei having the least bound neutron substituted by the Λ particle. The semi-realistic Afnan and Tang nucleon-nucleon potential and Bodmer and Usmani Λ-nucleon potential are adopted. The effect of many-body forces are considered by means either of a three body Λ-nucleon-nucleon potential of the Argonne type or of a density dependent modification of the Λ-nucleon interaction, fitted to reproduce the Λ binding energy in nuclear matter. While Jastrow correlations underestimate the attractive contribution of the three body Λ interaction, the density dependent potential provides a good description of the Λ binding energies over all the nuclear masses range, in spite of the relative simplicity of the model.

A study of the effects of short-range correlations over the (e, e ′ p) reaction for low missing energy in closed shell nuclei is presented. We use correlated, quasi-hole overlap functions extracted from the asymptotic behavior of the one-body density matrix, containing central correlations of Jastrow type, up to first-order in a cluster expansion, and computed in the very high asymptotic region, up to 100 fm. The method to extract the overlap functions is checked in a simple shell model, where the exact results are known. We find that the single-particle wave functions of the valence shells are shifted to the right due to the short-range repulsion by the nuclear core. The corresponding spectroscopic factors are reduced only a few percent with respect to the shell model. However, the (e, e ′ p) response functions and cross sections are enhanced in the region of the maximum of the missing momentum distribution due to short-range correlations.