Centrality Dependence of Chemical Freeze-out in Au+Au Collisions at RHIC

Abstract

We will report centrality dependence of chemical freeze-out temperature ($T_{ch}$), light quark chemical potential (${\mu }_q$), strange quark chemical potential (${\mu }_s$), and strangeness saturation factor (${\gamma }_s$) in Au+Au collisions at $\sqrt{s_{NN}}$ = 130 and 200 GeV. A systematic study for combination of ratios for chemical freeze-out fit is studied and we have found small ombination dependences. The results show ${\gamma }_s$ increasing with centrality but the other parameters have less sensitivity to the centralities.

6 pages, 3 figures. A write-up of a poster presented in the international conference Quark Matter 2004 at Oakland, CA