IN-MEDIUM KAON AND ANTIKAON PROPERTIES IN THE QUARK-MESON COUPLING MODEL

The properties of the kaon, K, and antikaon, (K) over bar, in nuclear medium are studied in the quark-meson coupling (QMC) model. Employing a constituent quark-antiquark (MIT bag model) picture, their excitatio n energies in a nuclear medium at zero momentum are calculated within mean field approximation. The scalar, and the vector mesons are assume d to couple directly to the nonstrange quarks and antiquarks in the K and (K) over bar mesons. It is demonstrated that the rho meson induces different mean field potentials for each member of the isodoublets, K and (K) over bar, when they are embedded in asymmetric nuclear matter . Furthermore, it is also shown that this rho meson potential is repul sive for the K- meson in matter with a neutron excess, and renders K- condensation less likely to occur. (C) 1998 Elsevier Science B.V. All rights reserved.