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Duality and Chiral Restoration from Dilepton Production in Relativistic Heavy-Ion Collisions

R. Rapp
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Abstract

We discuss the recent status in the theoretical understanding of dilepton production in central heavy-ion reactions with the Pb-beam at the full CERN-SpS energy of 158 AGeV. In the low-mass region ($M\le$~1 GeV) a strong broadening of the vector meson resonances in hot and dense matter (especially for the $ρ$ meson) entails thermal dilepton rates very reminiscent to perturbative $q\bar q$ annihilation close to the expected phase boundary of the chiral symmetry restoring transition. A consistent description of the experimentally observed enhancement at both low and intermediate masses (1.5 GeV~$\le M \le$~3 GeV) in terms of thermal radiation from an expanding fireball can be obtained.

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R. Rapp. 1999-09-22. Duality and Chiral Restoration from Dilepton Production in Relativistic Heavy-Ion Collisions. https://arxiv.org/abs/hep-ph/9909483

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