Dynamics of K̄ and multi-K̄ nuclei

We report on self-consistent calculations of single-K - nuclear states and multi-K̄-nuclear states in C12, O16, Ca40, and Pb208 within the relativistic mean-field (RMF) approach. Gradient terms motivated by the p-wave resonance Σ(1385) are found to play a secondary role for single-K - nuclear systems where the mean-field concept is acceptable. Significant contributions from the K̄N→πΛ conversion mode, and from the nonmesonic K̄NN→YN conversion modes, which are assumed to follow a ρ2 density dependence, are evaluated for the deep binding-energy range of over 100 MeV where the decay channel K̄N→πΣ is closed. Altogether we obtain K- total decay widths of 50-100 MeV for binding energies exceeding 100 MeV in single-K- nuclei. Multi-K̄-nuclear calculations indicate that the binding energy per K̄ meson saturates upon increasing the number of K̄ mesons embedded in the nuclear medium. The nuclear and K̄ densities increase only moderately and are close to saturation, with no indication of any kaon-condensation precursor.