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تسجيل مستخدم جديدChemical freeze-out parameters at RHIC from microscopic model calculations
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L.V. Bravina
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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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