Strangeness production in heavy ion collisions

Strangeness production in heavy ion collisions is discussed in a broad energy range from SIS to RHIC. %We emphasize that in the In the whole energy range particle yields are showing high level of chemical equilibration which can be described by the unified freezeout conditions of fixed energy/particle $\simeq 1$GeV. The statistical model within the canonical formulation of strangeness conservation provides a framework to describe the observed enhancement of (multi)strange particles from p+A to A+A collisions measured at the SPS energy and predicts that this enhancement should be larger for decreasing collision energy. However, only at the SPS and RHIC chemical freezeout temperature is consistent within error with the critical value required for deconfinement and simultaneously strangeness is uncorrelated and distributed in the whole volume of the fireball.