Abstract:
The per-event yield of the highest transverse momentum charged particle and charged-particle jet, integrated above a given pminTthreshold starting at pminT=0.8 and 1 GeV, respectively, is studied in collisions at The particles and the jets are measured in the pseudorapidity ranges and 1.9, respectively. The data are sensitive to the momentum scale at which parton densities saturate in the proton, to multiple partonic interactions, and to other key aspects of the transition between the soft and hard QCD regimes in hadronic collisions.