High pT pion and kaon production in relativistic nuclear collisions
Absztrakt:
High-p(T) pion and kaon production is studied in relativistic
proton-proton, proton-nucleus, and nucleus-nucleus collisions in
a wide energy range. Cross sections are calculated based on
perturbative QCD, augmented by a phenomenological transverse-
momentum distribution of partons ("intrinsic k(T)"). An energy
dependent width of the transverse-momentum distribution is
extracted from pion and charged hadron production data in
proton-proton/proton-antiproton collisions. Effects of
multiscattering and shadowing in the strongly interacting medium
are taken into account. Enhancement of the transverse-momentum
width is introduced and parameterized to explain the Cronin
effect. In collisions between heavy nuclei, the model
overpredicts central pion production cross sections (more
significantly at higher energies), hinting at the presence of
jet quenching. Predictions are made for proton-nucleus and
nucleus-nucleus collisions at relativistic heavy ion collider
energies.