Effects of retardation on normal and quasi-deuteron pairing in asymmetric nuclear matter

Full text. The main goal of this work is to study retardation effects in a relativistic version of the effective quasi-particle approximation and to verify their effect on the isoscalar and isovector pairing fields in relativistic nuclear matter. Both relativistic calculations and nonrelativistic calculations give extremely large isoscalar n-p pairing fields of about 10 MeV. Within an effective quasi-particle approximation we can take into account a part of the partial occupations seen in a self-consistent Greens function approach through the energy dependence of the Hartree-Fock-Bogoliubov mean fields. Nonrelativistic calculations performed in this approximation gives a reduction of the isoscalar n-p pairing field similar to that obtained in the self-consistent Greens function formalism. Here we investigate the retardation effects in Hartree-Fock-Bogoliubov approximation. (author)