QCD phase transition in multiparticle environment

Chiral QCD phase transition is examined in the environment of relativistic nuclear collisions. The effective potential, at T = T-c, of the O(4) universality class is used in order to formulate the Statistical Mechanics of primordial hadrons (masseless pions and sigmas) produced in heavy ion collisions. Critical fluctuations in rapidity space are revealed and their universal properties identified. A Monte Carlo simulation of the corresponding events (critical events) shows that the predictions of the theory are accessible to experimental observation.