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Probing nuclear expansion dynamics with $π^-/π^+$-spectra

S. Teis·W. Cassing·M. Effenberger·A. Hombach·U. Mosel·Gy. Wolf
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Abstract

We study the dynamics of charged pions in the nuclear medium via the ratio of differential $π^-$- and $π^+$-spectra in a coupled-channel BUU (CBUU) approach. The relative energy shift of the charged pions is found to correlate with the pion freeze-out time in nucleus-nucleus collisions as well as with the impact parameter of the heavy-ion reaction. Furthermore, the long-range Coulomb force provides a 'clock' for the expansion of the hot nuclear system. Detailed comparisons with experimental data for $Au + Au$ at 1 GeV/A and $Ni + Ni$ at 2.0 GeV/A are presented.

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S. Teis, W. Cassing, M. Effenberger, A. Hombach, U. Mosel, Gy. Wolf. 1997-01-28. Probing nuclear expansion dynamics with $π^-/π^+$-spectra. https://doi.org/10.1007/s002180050405

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