Hadronization in heavy ion collisions: recombination or fragmentation?

Abstract

We show that hadron production in relativistic heavy ion collisions at transverse momenta larger than 2 GeV/c can be explained by the competition of two different hadronization mechanisms. Above 5 GeV/c hadron production can be described by fragmentation of partons that are created perturbatively. Below 5 GeV/c recombination of partons from the dense and hot fireball dominates. This can explain some of the surprising features of RHIC data like the constant baryon-to-meson ratio of about one and the small nuclear suppression for baryons between 2 to 4 GeV/c.

Comments: Contribution to the 7th Conference on Strange Quark Matter (SQM 2003), submitted to J.Phys.G; 6 pages LaTeX, 4 eps figures, uses iopart.cls