Screening effects on the NN potential in relativistic nuclear matter

Abstract

We calculate the low-momentum NN effective potential as given by the one-boson exchange approximation inside a nuclear plasma, using the relativistic σ-ω model. The screening effects on the interparticle potential are first studied at zero temperature for different densities, and next at finite temperature. We discuss these effects at short (0 ⩽ r ⪅ 1 fm), intermediate (1 fm ⪅ r ⪅ 2 fm) and long (r ⪆ 2 fm) interparticle distances. As compared to the NN interaction in vacuum, important modifications are observed in the intermediate range, where the attractive potential well is reduced as density or temperature increases, and at long distances, where the potential shows Friedel-like oscillations instead of an exponential damping. We discuss the physical origin of these oscillations and analyse their behaviour with the thermodynamical state. From a qualitative point of view, this behaviour is shown to be model independent, and should be encountered in any realistic model of nuclear matter.