In-medium kaon and antikaon properties in the quark-meson coupling model

Abstract

The properties of the kaon, $K$, and antikaon, $\kbar$, in nuclear medium are studied in the quark-meson coupling (QMC) model. Employing a constituent quark-antiquark (MIT bag model) picture, their excitation energies in a nuclear medium at zero momentum are calculated within mean field approximation. The scalar, and the vector mesons are assumed to couple directly to the nonstrange quarks and antiquarks in the $K$ and $\kbar$ mesons. It is demonstrated that the $ρ$ meson induces different mean field potentials for each member of the isodoublets, $K$ and $\kbar$, when they are embedded in asymmetric nuclear matter. Furthermore, it is also shown that this $ρ$ meson potential is repulsive for the $K^-$ meson in matter with a neutron excess, and renders $K^-$ condensation less likely to occur.

Latex, 11 pages, 4 Postscript figures, a few typos which can be important for an interpretation (but not reflected in the results) are corrected, as published in (E) Phys. Lett. B 436 (1998) 453