  The RHIC beam energy scan program in its first phase collected data for Au+Au
collisions at beam energies of 7.7, 11.5 and 39 GeV. The event statistics
collected at these lower energies allow us to study the centrality dependence
of various observables in detail, and compare to fixed-target experiments at
SPS for similar beam energies. The chemical and kinetic freeze-out parameters
can be extracted from the experimentally measured yields of identified hadrons
within the framework of thermodynamical models. These then provide information
about the system at the stages of the expansion where inelastic and elastic
collisions of the constituents cease. We present the centrality dependence of
freeze-out parameters for Au+Au collisions at midrapidity for $\sqrt{s_{NN}} =
7.7$, 11.5, and 39 GeV from the STAR experiment. The chemical freeze-out
conditions are obtained by comparing the measured particle ratios (involving
$\pi$, $K$, $p$, and $\bar{p}$) to those from the statistical thermal model
calculations. The kinetic freeze-out conditions are extracted at these energies
by simultaneously fitting the invariant yields of identified hadrons ($\pi$,
$K$, and $p$) using Blast Wave model calculations.

Nuclear Experiment