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arXiv · 0704.1785

Three-body collisions in Boltzmann-Uehling-Uhlenbeck theory

A. B. Larionov·O. Buss·K. Gallmeister·U. Mosel
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Abstract

Aiming at a microscopic description of heavy ion collisions in the beam energy region of about 10 A GeV, we extend the Giessen Boltzmann-Uehling-Uhlenbeck (GiBUU) transport model by including a relativistic mean field, in-medium baryon-baryon cross sections and three-body collisions. The model is then compared with experimental data for central Au+Au collisions at 2-10 A GeV and central Pb+Pb collisions at 30 and 40 A GeV on the proton rapidity spectra, the midrapidity yields of $π^+$, $K^\pm$ and $(Λ+Σ^0)$, and the transverse mass spectra of $π^\pm$ and $K^\pm$. The three-body collisions increase the inverse slope parameters of the hadron $m_\perp$-spectra to a good agreement with the data.

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A. B. Larionov, O. Buss, K. Gallmeister, U. Mosel. 2007-09-24. Three-body collisions in Boltzmann-Uehling-Uhlenbeck theory. https://doi.org/10.1103/physrevc.76.044909

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