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arXiv · hep-ph/9907502

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

R. Rapp·J. Wambach
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Abstract

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 $q\bar q$ 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.

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R. Rapp, J. Wambach. 1999-07-26. Low-Mass Dileptons at the CERN-SpS: Evidence for Chiral Restoration?. https://doi.org/10.1007/s100500050364

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