PHASE-TRANSITION OF HOT NEUTRON MATTER TO PI-0-CONDENSED STATE

We investigate the equation of state (EOS) of hot neutron matter with pi-0-condensed state on the basis of the Alternating-Layer-Spin model by solving the Hartree-Fock equation at finite temperature. We find that the phase transition to pi-0-condensed state is suppressed considerably with temperature. We first calculate the entropy and specific heat of pi-0-condensed state and find that they are much lower than those of normal state. We also find that the effective mass of nucleons in normal and pi-0-condensed state is almost independent of temperature. The application to supernova explosions is discussed in detail, especially the evolution of the collapsing core along the iso-entropy line and its effects on the pressure.