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Chemical freeze-out parameters at RHIC from microscopic model calculations

L. V. Bravina·E. E. Zabrodin·S. A. Bass·A. Faessler·C. Fuchs·M. I. Gorenstein·W. Greiner·S. Soff·H. Stoecker·H. Weber
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Abstract

The relaxation of hot nuclear matter to an equilibrated state in the central zone of heavy-ion collisions at energies from AGS to RHIC is studied within the microscopic UrQMD model. It is found that the system reaches the (quasi)equilibrium stage for the period of 10-15 fm/$c$. Within this time the matter in the cell expands nearly isentropically with the entropy to baryon ratio $S/A = 150 - 170$. Thermodynamic characteristics of the system at AGS and at SPS energies at the endpoints of this stage are very close to the parameters of chemical and thermal freeze-out extracted from the thermal fit to experimental data. Predictions are made for the full RHIC energy $\sqrt{s} = 200$ AGeV. The formation of a resonance-rich state at RHIC energies is discussed.

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L. V. Bravina, E. E. Zabrodin, S. A. Bass, A. Faessler, C. Fuchs, M. I. Gorenstein, W. Greiner, S. Soff, H. Stoecker, H. Weber. 2001-04-06. Chemical freeze-out parameters at RHIC from microscopic model calculations. https://doi.org/10.1016/s0375-9474(01)01385-9

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