High-p T charged hadron suppression in Au+Au collisions at √s NN =200 GeV

The PHENIX experiment at the Relativistic Heavy Ion Collider has measured charged hadron yields at midrapidity over a wide range of transverse momenta (0.5 T NN =200 GeV. The data are compared to π 0 measurements from the same experiment. For both charged hadrons and neutral pions, the yields per nucleon-nucleon collision are significantly suppressed in central compared to peripheral and nucleon-nucleon collisions. The suppression sets in gradually and increases with increasing centrality of the collisions. Above 4-5 GeV/c in p T , a constant and almost identical suppression of charged hadrons and π 0 's is observed. The p T spectra are compared to published spectra from Au+Au at √s NN =130 in terms of x T scaling. Central and peripheral π 0 as well as peripheral charged spectra exhibit the same x T scaling as observed in p+p data.