Superfluidity with dressed nucleons

The gap equation with dressed propagators is solved in symmetric nuclear matter. Nucleon self-energies are obtained within the self-consistent in medium T matrix approximation. The off-shell gap equation is compared to an effective quasiparticle gap equation with reduced interaction. At normal density, we find a reduction of the superfluid gap from 6.5MeV to 0.45MeV when self-energy effects are included. superfluidity, nuclear matter 21.65.+f, 24.10.Cn, 26.60.+c The importance of pairing correlation in nuclear systems was realized very early [1]. In finite nuclei, pairing effects are known in the mass systematics of nuclei and the properties of deformed nuclei. In extended systems, nuclear pairing is expected to occur in the dense matter inside the neutron stars [2, 3]. Quantitative description of pairing correlations starting from bare nucleon-nucleon interactions is still limited. In medium effects, going beyond simple gap equation with free interaction, are important [4, 5, 6, 7, 8, 9, 10, 11, 12]. The use of the induced interaction in the gap equation was studied for neutron matter leading to a significant reduction of the pairing strength [4, 5, 6, 7]. Another effect is due to the dressing of nucleons in an interacting system, leading to a modification of the density of states and of the effective energy gap [8, 9, 10]. From the Bardeen-Cooper-Schrieffer result [13], it is obvious that self-energy effects modifying the effective mass change the value of the superfluid gap. Furthermore, the reduced quasiparticle strength at the Fermi surface leads to a modification of the effective pairing interaction [8, 9, 10]. Recently self-consistent in medium T matrix was calculated for nuclear matter [14, 15, 16, 17, 18, 19]. In this approach ladder diagrams with dressed particle-particle and hole-hole propagators are summed 〈p|T (P,Ω)|p ′ 〉 = V (p,p ′ ) + ∫