Hadrochemical vs. microscopic analysis of particle production and freeze-out in ultrarelativistic heavy ion collisions

摘要

The investigation of hot and dense nuclear matter in ultra-relativistic heavy-ion collisions in general~1,2,3 and the search for a deconfinement phase transition from hadronic to quark matter in particular~4,5,6,7, is one of the currently fastest moving research fiels of nuclear physics. Hadron abundances and ratios ahve been suggested as possible signatures for exotic states and phase transitions in dense nuclear matter. In addition they have been applied to study the degree of chemical equilibration in a relativistic heavy-ion reaction. Bulk properties like temperatures, entropies and chemical potnetials of highly excited hadronic matter have been extracted assuming thermal and chemical equilibrium~8,9,10,11,12,13,14.