Observable measures of critical behavior in high-energy nuclear collisions

Critical behaviors of quark-hadron phase transition in high-energy heavy-io n collisions are investigated with the aim of identifying hadronic observab les. The surface of the plasma cylinder is mapped onto a 2D lattice. The Is ing model is used to simulate configurations corresponding to cross-over tr ansitions in accordance to the findings of QCD lattice gauge theory. Hadron s are formed in clusters of all sizes. Various measures are examined to qua ntify the fluctuations of the cluster sizes and of the voids among the clus ters. The canonical power-law behaviors near the critical temperature are f ound for appropriately chosen measures. Since the temperature is not direct ly observable, attention is given to the problem of finding observable meas ures. It is demonstrated that for the measures considered the dependence on the final-state randomization is weak. Thus the critical behavior of the m easures proposed is likely to survive the scattering effect of the hadron g as in the final state.