Antikaon Condensation and Hyperons Production in Protoneutron Stars

A chiral hadronic model is extended to investigate antikaon condensation and hyperons production of protoneutron stars.Our results show that neutrino trapping makes the critical density of K~-condensation delay to higher density and ~0 condensation not occur.Meanwhile,the equation of state(EOS) of(proto)neutron star matter considering neutrino trapping is stiffer than the case without neutrino trapping.Therefore the maximum masses of protoneutron stars with neutrino trapping are larger than those without neutrino trapping.If hyperons are considered,antikaon condensation does not appear in(proto)neutron stars.Meanwhile,the corresponding EOS becomes much softer,and the maximum masses of(proto)neutron stars are smaller than those without hyprons.