Low-Mass Dilepton Enhancement from in-Medium Hadronic Interactions
نویسنده
چکیده
Based on a realistic model for the meson in free space we investigate its medium modiications through rescattering in a hot hadron gas. Within the vector dominance model the corresponding in-medium spectral function is applied to calculate e + e ? spectra in central Pb+Au as measured by the CERES collaboration at CERN-SpS energies; we also compare to results obtained with the assumption of a 'dropping mass' and discuss possible observables to distinguish the two mechanisms , e.g. dilepton q t spectra. Finally our in-medium propagator is employed to analyse recent dilepton spectra from the DLS collaboration in Ca+Ca at BEVALAC energies.
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Low-mass Dileptons from In-medium Hadronic Interactions
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