  We find that collective flow model which can successfully analyze charged
particle distributions at AGS and lower SPS (less than 20Gev/n). but fails to
analyze that of at RHIC. The tails of distribution of charged particle at RHIC
has a jump from the collective flow model calculation as the energy increases.
Thermalization Component Model is presented based on collective flow to study
the multiplicity distributions at RHIC in this paper. It is realized that the
region of phase space of collective flow can reflect that of thermalization
region. By comparing the contributions of particle productions from
thermalization region at different energies and different centralities, we can
deepen our study on the feature of collective movement at RHIC.
  Keywords: Thermalization, Thermalization component model
