Kaon-Condensed Hypernuclei

from hyperonic matter, where hyperons (Y==A, X-) are mixed in addition to the neutrons, protons and leptons in the ground state of neutron-star matter.5) It has been shown that the equation of state CEOS) of the kaon-condensed phase becomes considerably soft owing to the (anti) kaon-baryon attractions in addition to the softening effect by mixing of hyperons. On the other hand, the stiffriess of the EOS is recovered at high densities due to the repulsive interaction between baryons. As a result, the energy of the system has a local minimum, which suggests the existence of the self-bound objects with kaon condensates. Based on the EOS, we have discussed the structure of the kaon-condensed neutron star as a selfbound star and its implications for observations of mass-radius relations.