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arXiv · 0911.4439

Non-equilibrium approaches to the pre-thermal and post-hadronisation stages of A+A collisions

Yu. M. Sinyukov·Iu. A. Karpenko
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Abstract

The results related to non-equilibrium phenomena at the very early and late stages of the processes of A+A collisions are presented. A good description of the hadron momentum spectra as well as pion and kaon interferometry data at RHIC is reached within the realistic dynamical picture of A+A collisions: HydroKinetic Model (HKM). The model accumulates the following features: not too early thermalization time; $\tau\geq 1$ fm/c; a developing of the pre-thermal transverse flows; the effectively more hard, than in the case of chemical equilibrium, equation of state of expanding chemically non-equilibrated multi-hadronic gas; a continuous non-equilibrated emission of hadrons. All these factors lead to a good description of the mentioned RHIC data, in particular, the observed $R_{out}/R_{side}$ ratios, solving, therefore, the HBT puzzle in detailed realistic model.

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Yu. M. Sinyukov, Iu. A. Karpenko. 2009-11-23. Non-equilibrium approaches to the pre-thermal and post-hadronisation stages of A+A collisions. https://arxiv.org/abs/0911.4439

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