Medium modifications of antikaons in dense matter

Abstract

We investigate the modification of antikaons in isospin symmetric and asymmetric nuclear matter. Using the leading s-wave couplings of the SU(3) chiral meson-baryon Lagrangian we solve the coupled channel kaon-nucleon scattering equation selfconsistently. The in-medium antikaon propagator is calculated for different densities and different proton/neutron ratios. The spectral function of the antikaon is found to be broadened strongly, and its mass is shifted downward significantly. However, comparing the effective in-medium mass of the antikaon to the relevant charge chemical potential of neutron star matter, we find that kaon condensation is unlikely to occur in neutron stars.

Comments: 29 pages, 35 figures; v2: additional curves for symmetric matter in Figs 14,15; references added