  Thermal model fit indicates early chemical freeze-out of multi-strange
hadrons with small collective velocities at 200AGeV Au-Au collisions at RHIC.
In this work, we present our recent results by SPheRIO hydrodynamical
calculations inspired by this picture. In our model, multi-strange hadrons go
through chemical freeze-out when the system reaches some temperature close to
the phase transition, stopping to make inelastic collisions, and their
abundances are therefore determined only by partonic EOS. At a lower
temperature thermal freeze-out takes place where elastic collisions are brought
to a halt. We calculate the spectra for various hadrons at different centrality
windows, with chemical and thermal freeze-out temperature being fit as a
function of centrality. As it is shown, the result provides a reasonable
panoramic description of the spectra of identified particles. Chemical
freeze-out gives good correction of the multiplicity of certain species of
particles, especially for multi-strange hadrons.
