Nuclear Potentials Relevant to the Symmetry Energy in Chiral Models

We employ the extended Nambu-Jona-Lasinio (NJL), linear-σ models, and density-dependent model with chiral limits to work out mean fields relevant properties of nuclear matter. To have constraint from data, we re-examine Dirac optical potentials symmetry potential based on relativistic impulse approximation (RIA). Unlike NJL models limit in terms vanishing scalar density, a sluggish changing field loses at high-density end. The various can characterize different Schrödinger-equivalent kinetic energy whole density region intermediate region. drop due restoration results clear rise energy. gives softening thereof high densities.