Cronin Effect and High Transver Momentum Suppression in D+Au Collisions

Abstract

Great interest has attached to recent D+Au, s^(1/2) = 200 A GeV data at RHIC, obtained with the BRAHMS detector. Between pseudorapidity eta=0 and eta=3.2 the appropriately defined ratio R[DAu/PP], comparing transverse momentum spectra of D+Au to P+P exhibits a steady decrease with eta. This diminuition is examined within a two-stage simulation, the last stage being a purely hadronic, reduced energy cascade. The result is an adequate description of the data including the so-called Cronin effect. Additionally there is clear evidence for suppression, in the second stage, of relatively high transverse momentum, eta=0, leading mesons, i.e. the Cronin effect, only near mid-rapidity, is appreciably muted by final state interactions.