Model Investigation of Non-Thermal Phase Transition in High Energy Collisions

The Non-thermal phase transition in high energy collisions is studied in some detail in the framework of random cascade model. The relation between the characteristic parameter $\lambda_q$ of phase transition and the rank $q$ of moment is obtained using Monte Carlo simulation, and the existence of two phases in self-similarly cascading multiparticle systems is shown. The relation between the critical point $q_c$ of phase transition on the fluctuation parameter $\alpha$ is obtained and compared with the experimental results from NA22. The same study is carried out also by analytical calculation under central limit approximation. The range of validity of the central limit approximation is discussed.