Effects of Correlations in Medium and High Energy Scattering Off Nuclei

The linked cluster expansion technique, introduced for the calculation of ground-state properties of nuclear systems, has been applied to the calculation of diagonal and non diagonal one- and two-body density matrices of nuclei ranging from $^{3}He$ to $^{208}Pb$. The results for few-body systems agree with Variational Monte Carlo results. Diagonal and non-diagonal density matrices appear in exclusive medium energy processes as $A(e,e'2N)X$ reactions, as well as correlation corrections in many high energy hadronic scattering processes, usually treated within the single-density approximation of Glauber theory. The realistic two-body densities have been used to calculate $(e,e'p)$ and $(e,e'pp)$ processes off few-nucleon systems and complex nuclei, the p-p and p-n momentum distributions in medium-weight nuclei, the total elastic, inelastic and quasi-elastic hadron-nucleus cross sections at high energies, finding relevant effects from short range and tensor correlations.