Anomalous Anti-proton to Negative Pion Ratio as Revealed by Jet Quenching at RHIC

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We study the apparent discrepancy between the standard PQCD predictions for the meson and baryon ratios and multiplicities at moderate high pₜ > 2 GeV and recent experimental measurements in Au+Au collisions at √sNN=130 GeV at the Relativistic Heavy Ion Collider (RHIC). We show that the differences, most pronounced in central collisions, can be explained by a strong non-perturbative baryon Junction component, which dominates the currently accessible experimental pₜ window and the non-abelian energy loss of fast partons propagating through hot and dense medium. The recently introduced two component hybrid model, which combines a quenched jet PQCD calculation in the Gyulassy-Levai-Vitev (GLV) formalism and a phenomenological "soft" part, is further elaborated to take into account the full 3D expansion in the pre-hadronization phase and include particle flavor dependent "soft" inverse slopes as suggested by the baryon Junction picture. We show that such approach can resolve what seems to be a factor of ≃ 2 difference in the moderate high pₜ suppression of π⁰ and h- as recently reported by the PHENIX collaboration. The observed quenching of the high pₜ particle spectra and the large p/π- and p/π+ ratios as a function of pₜ are found to be consistent with a creation of a deconfined phase and non-abelian energy loss of fast partons in a plasma of initial gluon rapidity density dNᵍ/dy 1000.