Pion condensation at finite temperature. Pt. 2

We calculate, in several increasingly complex models, the threshold for charged pion condensation in neutron-rich matter at finite temperature, including effects of thermal excitations have two important effects: first, to modify the phase diagram qualitatively from that predicted by mean field theory, and second, to make the phase transition to a nonuniform condensed state at finite temperature always first, rather than second, order. (orig.)