Systematics of Identified Particle Production in pp, dAu and Au-Au Collisions at RHIC Energies

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(Abstract is abridged for arXiv.) Identified mid-rapidity particle spectra and freeze-out properties are presented for 200 GeV pp, 200 GeV dAu and 62.4 GeV Au-Au collisions, measured in the STAR-TPC.

• Evolution of the identified particle spectra ($\pi^{\pm}$, $K^{\pm}$, p and $\overline{p}$) with charged particle multiplicity and event centrality is investigated in detail.
• Thermal model fits to the measured particle ratios yield a chemical freeze-out temperature $\sim$ 155 MeV in 200 GeV pp, 200 GeV dAu and 62.4 GeV Au-Au collisions.
• The extracted chemical freeze-out temperature is close to the critical phase transition temperature predicted by lattice QCD calculations.