Low-Mass Dileptons at the CERN-SpS: Evidence for Chiral Restoration?

الأصل · EN

Using a rather complete description of the in-medium ρ spectral function - being constrained by various independent experimental information - we calculate pertinent dilepton production rates from hot and dense hadronic matter. The strong broadening of the ρ resonance entails a reminiscence to perturbative q q annihilation rates in the vicinity of the phase boundary. The application to dilepton observables in Pb(158AGeV)+Au collisions - incorporating recent information on the hadro-chemical composition at CERN-SpS energies - essentially supports the broadening scenario. Possible implications for the nature of chiral symmetry restoration are outlined.