Perturbative QCD Results on Pion Production in pp, pA and AA Collisions

Abstract

We summarize new pQCD results on pion production in proton-proton (pp), proton-nucleus (pA) and nucleus-nucleus (AA) collisions. Our calculation introduces intrinsic parton transverse momentum (k_T) and is performed effectively at next-to-leading order (NLO), applying a K factor extracted for jet events. Two different factorization scales, Q=p_{T,jet}/2 and p_{T,jet} are used. Experimental data in pA collisions imply a preference for the latter choice at NLO level. We display our results at CERN SPS for AA collisions.

Talk given at Budapest Workshop on Quark and Hadron Dynamics in Relativistic Heavy Ion Collisions (BP 2002) Budapest, Hungary, 3-7 Mar 2002. 11 pages in Latex, 7 PS figure. Submitted to Heavy Ion Physics