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arXiv · 1009.0701

Indications of early thermalization in relativistic heavy-ion collisions

Piotr Bozek·Iwona Wyskiel-Piekarska
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Abstract

The directed flow of particles emitted from the fireball created in a heavy-ion collision is shown to be a very sensitive measure of the pressure equilibration in the first 1 fm/c of the evolution. Performing a 3+1 dimensional relativistic hydrodynamic calculation with nonequilibrated longitudinal and transverse pressures, we show that the directed flow is strongly reduced if the pressure imbalance survives for even a short time. Transverse momentum spectra, elliptic flow and interferometry correlation radii are not very sensitive to this early pressure anisotropy. Comparison with the data points toward a short equilibration time of the order of $0.25$fm/c or less.

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Piotr Bozek, Iwona Wyskiel-Piekarska. 2010-09-03. Indications of early thermalization in relativistic heavy-ion collisions. https://doi.org/10.1103/physrevc.83.024910

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