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A unique parametrization of the shapes of secondary dilepton spectra observed in central heavy-ion collisions at CERN-SPS energies

K. Gallmeister·B. Kämpfer·O. P. Pavlenko·C. Gale
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Abstract

A unique parametrization of secondary (thermal) dilepton yields in heavy-ion experiments at CERN-SPS is proposed. This parametrization resembles a thermal $q \bar q$ annihilation rate. This is inspired by the observation that lepton pair production rates are quantitatively similar, whether expressed in a hadronic or partonic basis. Adding the thermal yield and the background contributions (hadronic cocktail, Drell-Yan, correlated semileptonic decays of open charm) the spectral shapes of the CERES/NA45, NA38, NA50 and HELIOS/3 data from experiments with lead and sulfur beams can be well described.

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K. Gallmeister, B. Kämpfer, O. P. Pavlenko, C. Gale. 2000-11-08. A unique parametrization of the shapes of secondary dilepton spectra observed in central heavy-ion collisions at CERN-SPS energies. https://doi.org/10.1016/s0375-9474(00)00584-4

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