Production of Charged Pions and Hadrons in Au+Au Collisions at sqrt(s_NN)=130GeV

Abstract

The STAR experiment has measured the production of charged hadrons and identified charged pions as a function of transverse momentum, (pseudo-)rapidity, and centrality in Au+Au collisions at sqrt(s_NN)=130GeV. The mean transverse momentum of charged hadrons(pions) increases by roughly 22%(15%) from peripheral to central collisions. As a function of (pseudo-)rapidity, the measured yields and spectral shapes are consistent with a Lorentz-boost invariant mid-rapidity region at least within |y|<0.5 for all collision centralities. We compare our measurements of the integrated charged particle (pseudo)-rapidity density per participating nucleon-pair with two models representing different phenomenological concepts of particle production and featuring opposing parameterizations of the centrality dependence of the rapidity density. We furthermore explore the discriminating power of our measurement against the theoretical calculations in the light of uncertainties originating from the determination of the average number of participating nucleons <Npart>.