Universal chemical freeze-out as a phase transition signature
Abstract
It is shown that kinetic freeze-out in relativistic heavy-ion collisions invariably entails a non-trivial dependence of the freeze-out temperature on the collision centrality. The centrality independence of the chemical freeze-out temperature observed in Au+Au collisions at RHIC is therefore inconsistent with the hypothesis that hadron abundances decouple kinetically from inelastic hadron-hadron interactions. On the other hand, it is consistent with the hypothesis that chemical decoupling is driven by the quark-hadron phase transition, and that the observed universal chemical freeze-out reflects its critical temperature, independent of the dynamical state of the collision fireball as it passes through the phase transition.
Keywords
Cite
@article{arxiv.nucl-th/0612105,
title = {Universal chemical freeze-out as a phase transition signature},
author = {Ulrich Heinz and Gregory Kestin},
journal= {arXiv preprint arXiv:nucl-th/0612105},
year = {2009}
}
Comments
16 pages, 4 figures. Talk given at the International Workshop on "Critical Point and Onset of Deconfinement", July 3-6, 2006, Galileo Galilei Institute, Florence, Italy. To appear in Proceedings of Science