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Enhanced Production of Low-Mass Electron Pairs in 40 AGeV Pb-Au Collisions at the CERN SPS

D. Adamova·CERES/NA45 Collaboration
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Abstract

We report on first measurements of low-mass electron pairs in Pb-Au collisions at the lower SPS beam energy of 40 AGeV. The pair yield integrated over the range of invariant masses 0.2 e+ e- annihilation with a modified rho-propagator. They may be linked to chiral symmetry restoration and support the notion that the in-medium modifications of the rho are more driven by baryon density than by temperature.

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D. Adamova, CERES/NA45 Collaboration. 2004-05-26. Enhanced Production of Low-Mass Electron Pairs in 40 AGeV Pb-Au Collisions at the CERN SPS. https://doi.org/10.1103/physrevlett.91.042301

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