Suppression of high transverse momentum hadrons at RHIC by (pre-) hadronic final state interactions

摘要

We investigate transverse hadron spectra from proton+proton, deuteron+Au andAu+Au collisions at sqrt{s}=200 GeV and 17.3 GeV within theHadron-String-Dynamics (HSD) approach which is based on quark, diquark, stringand hadronic degrees of freedom as well as Pythia calculations for the high pTspectra. The comparison to experimental data on transverse mass spectra fromp+p, d+Au and Au+Au reactions shows that pre-hadronic effects are responsiblefor both the hardening of the spectra for low transverse momenta (Cronineffect) as well as the suppression of high pT hadrons. The interactions offormed hadrons are found to be negligible in central Au+Au collisions atsqrt{s}=200 GeV for pT\geq 6 GeV/c, but have some importance for the shape ofthe ratio R_{AA} at lower pT values (\leq 6 GeV/c). The large suppression seenexperimentally is attributed to the inelastic interactions of 'leading'pre-hadrons with the dense environment, which could be partly of coloredpartonic nature in order to explain the large attenuation seen in most centralAu+Au collisions.