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Hadronic freeze-out following a first order hadronization phase transition in ultrarelativistic heavy-ion collisions

S. A. Bass·A. Dumitru·M. Bleicher·L. Bravina·E. Zabrodin·H. Stoecker·W. Greiner
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Abstract

We analyze the hadronic freeze-out in ultra-relativistic heavy ion collisions at RHIC in a transport approach which combines hydrodynamics for the early, dense, deconfined stage of the reaction with a microscopic non-equilibrium model for the later hadronic stage at which the hydrodynamic equilibrium assumptions are not valid. With this ansatz we are able to self-consistently calculate the freeze-out of the system and determine space-time hypersurfaces for individual hadron species. The space-time domains of the freeze-out for several hadron species are found to be actually four-dimensional, and differ drastically for the individual hadrons species. Freeze-out radii distributions are similar in width for most hadron species, even though the Omega-baryon is found to be emitted rather close to the phase boundary and shows the smallest freeze-out radii and times among all baryon species. The total lifetime of the system does not change by more than 10% when going from SPS to RHIC energies.

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S. A. Bass, A. Dumitru, M. Bleicher, L. Bravina, E. Zabrodin, H. Stoecker, W. Greiner. 1999-08-25. Hadronic freeze-out following a first order hadronization phase transition in ultrarelativistic heavy-ion collisions. https://doi.org/10.1103/physrevc.60.021902

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