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arXiv · 0912.4180

Matching of nonthermal initial conditions and hydrodynamic stage in ultrarelativistic heavy-ion collisions

S. V. Akkelin·Yu. M. Sinyukov
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Abstract

A simple approach is proposed allowing actual calculations of the preequilibrium dynamics in ultrarelativistic heavy-ion collisions to be performed for a far-from-equilibrium initial state. The method is based on the phenomenological macroscopic equations that describe the relaxation dynamics of the energy-momentum tensor and are motivated by Boltzmann kinetics in the relaxation-time approximation. It gives the possibility to match smoothly a nonthermal initial state to the hydrodynamics of the quark gluon plasma. The model contains two parameters, the duration of the prehydrodynamic stage and the initial value of the relaxation-time parameter, and allows one to assess the energy-momentum tensor at a supposed time of initialization of the hydrodynamics.

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S. V. Akkelin, Yu. M. Sinyukov. 2010-06-10. Matching of nonthermal initial conditions and hydrodynamic stage in ultrarelativistic heavy-ion collisions. https://doi.org/10.1103/physrevc.81.064901

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