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Thermal analysis of particle ratios and p_T spectra at RHIC

Wojciech Florkowski·Wojciech Broniowski·Mariusz Michalec
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Abstract

The thermal model of particle production is used to analyze the particle ratios and the p_T spectra measured recently at RHIC. Our fit of the particle ratios yields the temperature at the chemical freeze-out T_chem = 165 +- 7 MeV with the corresponding baryon chemical potential mu^B_chem = 41 +- 5 MeV. The quality of the fit shows that the model works well for RHIC. The p_T spectra are evaluated in an approach which takes into account the modifications of the initial thermal distributions by the secondary decays of resonances. All two- and three-body decays are included. This leads to an effective ``cooling'' of the spectra in the data region by about 35-40 MeV. We find that the pion spectrum is characterized by the inverse slope which agrees well with the value inferred from the RHIC data.

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Wojciech Florkowski, Wojciech Broniowski, Mariusz Michalec. 2001-12-14. Thermal analysis of particle ratios and p_T spectra at RHIC. https://arxiv.org/abs/nucl-th/0106009

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