Dense K-bar nuclei and their excited states

We have investigated the excited states as well as the ground state of various K-bar nuclei, based on the improved version of antisymmetrized molecular dynamics method with a phenomenological K-barN interaction. Our calculation shows that the ground state of K-bar nuclei forms dense state; more than 4 ρ0 (ρ0 being normal density). The two excited states of 11CK-, (Jπ, T) = (1/2+, 0) and (1/2+, 1), are also deeply bound below the Σπ-emission threshold. They are the same Jπ state but have quite different structures from each other; T=0 state has a well-developed clustering structure, while T=1 state has a shell-like structure. (author)