We investigate dynamics of the chiral transition in expanding quark-antiquark
plasma produced in an ultra-relativistic heavy ion collision. The chiral
symmetry break-down and dynamical generation of the constituent quark mass are
studied within the linear sigma model and Nambu-Jona-Lasinio model. Time
dependence of the quark and antiquark densities is obtained from the scaling
solution of the relativistic Vlasov equation. Fast initial growth and strong
oscillations of the constituent quark mass are found in the linear sigma model
as well as in the NJL model, when derivative terms are taken into account.Comment: 7 pages, Latex. To appear in Physics Letters
