Reheating after Supercooling in the Chiral Phase Transition

The chirally symmetric quark-gluon plasma produced in energetic heavy-ion collisions is predicted to supercool at the late stages of its evolution. The thermal energy is then transformed into the potential energy associated with an energetically unfavorable field configuration. Since the system is in an unstable state it eventually rolls down to the true minimum of the effective chiral potential. When this motion is described in terms of the sigma-model, we find that the energy of the coherent $\sigma-$field is very efficiently converted into pionic excitations due to anharmonic oscillations around this minimum. The system is expected to partially thermalize before its disintegration.