Effects of flavor asymmetric media on pion and kaon properties

Abstract

We investigate the behaviour of pion and kaon properties in dense asymmetric and neutron matter in the context of a generalized three-flavor Nambu-Jona-Lasinio model, focussing mainly on Pauli blocking and Fermi sea effects. Two main features are discussed: the splitting between charged mesons and the appearance at a low density of low-lying modes which are excitations of the Fermi sea. The contribution of the low-lying modes to the satisfaction of PCAC relations becomes more and more important as the density increases.