The statistical model of hadrogenesis in AA collisions from AGS to SPS and RHIC

We discuss experimental data on particle yields and particle spectra obtained in heavy ion collisions in a very broad energy range from SIS/GSI (√(s)≅2 GeV) through AGS/BNL (√(s)≅5 GeV) up to SPS/CERN (√(s)≅20 GeV) and RHIC/BNL (√(≅130)) GeV. We argue that in this broad energy range hadronic yields and their ratios resemble a thermal equilibrium population along unified freezeout curve determined by the condition of fixed energy/particle ≅ 1 GeV. At RHIC and top SPS thermal parameters are consistent within error with the critical conditions required for deconfinement. This, together with the particular distribution of strangeness within collision fireball, could indicate that chemical equilibrium is a direct consequence of parton to hadron transition which populates a state of maximum entropy. At lower energies equilibration in AA collisions should appear through hadronic interactions and rescatterings