How Disoriented Chiral Condensates Form: Quenching vs. Annealing
  We demonstrate that semiclassical fluctuations, their relaxation, and the chiral phase transition are automatically incorporated in the numerical simulations of the classical equations of motion in the linear $\sigma$-model when longitudinal and transverse expansions are included. We find that domains of disoriented chiral condensate with 4--5 fm in size can form through a quench while an annealing leads to domains of smaller sizes. We also demonstrate that quenching cannot be achieved by relaxing a chirally symmetric system through expansion. 
Masayuki Asakawa, Zheng Huang, and Xin-Nian Wang