11 09 2 v 1 8 N ov 2 00 5 Energy and system size dependence of chemical freeze - out in relativistic nuclear collisions
نویسنده
چکیده
We present a detailed study of chemical freeze-out in p-p, C-C, Si-Si and Pb-Pb collisions at beam momenta of 158A GeV as well as Pb-Pb collisions at beam momenta of 20A, 30A, 40A and 80A GeV. By analyzing hadronic multiplicities within the statistical hadronization model, we have studied the parameters of the source as a function of the number of the participating nucleons and the beam energy. We observe a nice smooth behaviour of temperature, baryon chemical potential and strangeness under-saturation parameter as a function of energy and nucleus size. Interpolating formulas are provided which allow to predict the chemical freeze-out parameters in central collisions at centre-of-mass energies √ sNN ∼ 4.5 GeV and for any colliding ions. Specific discrepancies between data and model emerge in particle ratios in Pb-Pb collisions at SPS between 20A and 40A GeV of beam energy which cannot be accounted for in the considered model schemes.
منابع مشابه
ar X iv : h ep - p h / 05 11 09 2 v 2 1 6 N ov 2 00 5 Energy and system size dependence of chemical freeze - out in relativistic nuclear collisions
We present a detailed study of chemical freeze-out in p-p, C-C, Si-Si and Pb-Pb collisions at beam momenta of 158A GeV as well as Pb-Pb collisions at beam momenta of 20A, 30A, 40A and 80A GeV. By analyzing hadronic multiplicities within the statistical hadronization model, we have studied the parameters of the source as a function of the number of the participating nucleons and the beam energy....
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The present knowledge about hadrons produced in relativistic heavy ion collisions is compatible with chemical freeze-out happening when the energy density divided by the particle density reaches the value of 1 GeV. This observation is used to determine the energy dependence of the chemical freeze-out parameters Tch and μ ch B for beam energies varying between 1 and 200 A·GeV. The consequences o...
متن کاملar X iv : n uc l - th / 9 90 30 63 v 2 2 0 Ju l 1 99 9 Chemical and Thermal Freeze - Out Parameters
The present knowledge about hadrons produced in relativistic heavy ion collisions is compatible with chemical freeze-out happening when the energy density divided by the particle density reaches the value of 1 GeV. This observation is used to determine the energy dependence of the chemical freeze-out parameters Tch and μ ch B for beam energies varying between 1 and 200 A·GeV. The consequences o...
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