Cluster structure of disoriented chiral condensate in rapidity distribution

We study the creation of disoriented chiral condensates with some initial boundary conditions that may be expected in high energy collisions. The equations of motion in the linear $\sigma$ model are solved numerically with and without a Lorentz-boost invariance. We suggest that a distinct cluster structure of coherent pion production in the rapidity distribution may emerge due to a quench and may be observed in experiments.