1995/08/04 by W. Cassing, W. Ehehalt, Che Ming Ko +1
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph
paper · pdf · doi:10.1016/0370-2693(95)01214-b
published as Phys.Lett. B363 (1995) 35-40 · 1 compressed uuencoded postscript file with 6 figures included, 18 pages
arxiv created 1995/08/04 · openalex publication_date 1995/11/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present a nonperturbative dynamical study of e+e- production in proton- nucleus and nucleus-nucleus collisions at SPS energies on the basis of a covariant transport approach. For p + A reactions the dilepton yield for invariant masses m ≤ 1.2 GeV is found to be dominated by the decays of the η, ρ, ω and Φ mesons in line with the findings of the CERES collaboration. For S + Au collisions at 200 GeV/A the dilepton yield is, however, dominated by π+π- annihilation due to the high pion densities achieved. Whereas for `free' meson masses and form factors the experimental cross section is slightly underestimated for 0.3 GeV ≤ m ≤ 0.45 GeV, different medium modifications of the ρ-meson appear compatible with current CERES data.