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Statistical description with anisotropic momentum distributions for hadron production in nucleus-nucleus collisions

B. Schenke·C. Greiner
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Abstract

The various experimental data at AGS, SPS and RHIC energies on hadron particle yields for central heavy ion collisions are investigated by employing a generalized statistical density operator, that allows for a well-defined anisotropic local momentum distribution for each particle species, specified by a common streaming velocity parameter. The individual particle ratios are rather insensitive to a change in this new intensive parameter. This leads to the conclusion that the reproduction of particle ratios by a statistical treatment does not imply the existence of a fully isotropic local momentum distribution at hadrochemical freeze-out, i.e. a state of almost complete thermal equilibrium.

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B. Schenke, C. Greiner. 2004-02-11. Statistical description with anisotropic momentum distributions for hadron production in nucleus-nucleus collisions. https://doi.org/10.1088/0954-3899%2F30%2F5%2F004

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