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Low-Mass $e^+e^-$ Pairs from in-Medium $ρ$ Meson Propagation

R. Rapp·G. Chanfray·J. Wambach
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Abstract

Based on a realistic model for the rho meson in free space we investigate it's medium modifications in a hot hadron gas generated by hadronic rescattering processes, i.e. renormalization of intermediate two-pion states as well as direct rho meson scattering off hadrons. Within the vector dominance model the resulting in-medium rho spectral function is applied to calculate $e^+e^-$ spectra as recently measured in heavy-ion collisions at CERN-SpS energies in the CERES experiment.

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R. Rapp, G. Chanfray, J. Wambach. 1997-01-30. Low-Mass $e^+e^-$ Pairs from in-Medium $ρ$ Meson Propagation. https://arxiv.org/abs/nucl-th/9701064

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