High Energy Hadron Production, Self-Organized Criticality and Absorbing State Phase Transition

Abstract

In high energy nuclear collisions, production rates of light nuclei agree with the predictions of an ideal gas at a temperature $T=155 \pm 10$ MeV. In an equilibrium hadronic medium of this temperature, light nuclei cannot survive. In this contribution, we suggest that the observed behavior is due to an evolution in global non-equilibrium, leading to self-organized criticality and to hadron formation as an absorbing state phase transition for color degrees of freedom. At the confinement point, the initial quark-gluon medium becomes quenched by the vacuum, breaking up into all allowed free hadronic and nuclear mass states, without (or with a very short-live) subsequent formation of thermal hadronic medium.