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arXiv · nucl-ex/0310004

Identified particle distributions in pp and Au+Au collisions at sqrt{s_NN}=200 GeV

Abstract

Transverse mass and rapidity distributions for charged pions, charged kaons, protons and antiprotons are reported for sqrt{s_NN}=200 GeV pp and Au+Au collisions at RHIC. The transverse mass distributions are rapidity independent within |y|<0.5, consistent with a boost-invariant system in this rapidity interval. Spectral shapes and relative particle yields are similar in pp and peripheral Au+Au collisions and change smoothly to central Au+Au collisions. No centrality dependence was observed in the kaon and antiproton production rates relative to the pion production rate from medium-central to central collisions. Chemical and kinetic equilibrium model fits to our data reveal strong radial flow and relatively long duration from chemical to kinetic freeze-out in central Au+Au collisions. The chemical freeze-out temperature appears to be independent of initial conditions at RHIC energies.

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BibTeXRIS

STAR Collaboration, J. Adams. 2003-10-06. Identified particle distributions in pp and Au+Au collisions at sqrt{s_NN}=200 GeV. https://doi.org/10.1103/physrevlett.92.112301

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