LOCAL ENERGY DENSITY-FUNCTIONAL AND DENSITY-DEPENDENT PAIRING IN NUCLEAR SYSTEMS

An approach based on the local energy density functional method for de scribing the ground-state properties of superfluid nuclei is presented . A generalized variational principle is formulated which corresponds, in the weak pairing approximation, to a full treatment of the Hartree -Fock-Bogoliubov problem with an effective contact pairing interaction . The Gor'kov equations for generalized Green's functions are treated exactly in the coordinate-space representation. The method is used to calculate the differential observables including odd-even mass differe nces and odd-even effects in charge radii which turn out to be very se nsitive to the density dependence of the effective pairing force. A be tter knowledge of this density dependence allows one to make predictio ns for the pairing gap at the Fermi surface as a function of nuclear m atter density. (C) 1998 American Institute of Physics. [S0021-3640(98) 00216-3].