Centrality Dependence of Inclusive Identified Hadrons in PHENIX

Results of identified charged hadrons produced in Au+Au collisions at $\sqrt{s_{NN}}=130$ GeV as a function of centrality are discussed. The $<p_T>$ of protons and antiprotons is significantly larger than in p–p collisions at the same center of mass energy. Its scaling with the number of participant nucleons, an increase of $20\pm 5$ from peripheral to central, may be due to radial expansion. In a hydrodynamical picture a simultaneous fit of pions, kaons and protons is consistent with a radial flow velocity of ${\beta }_{\mathrm{T}\mathrm{s}\mathrm{u}\mathrm{r}\mathrm{f}\mathrm{a}\mathrm{c}\mathrm{e}}=0.72\pm 0.01$ and a temperature of $T=122\pm 4$ MeV for the 5% most central collisions. Dominant proton yields at ${p_{T}} > 1.5$GeV\mathrm{/}candantiprotonyieldsat${p_{T}} > 1.8$ GeV/c may be explained by a combination of suppression of pion yields at high $p_T$ and the boost of low $p_T$ protons to high $p_T$ from radial flow.