2000/10/31 by Amand Faessler, C. Fuchs, Christian Fuchs +4
Physics and Astronomy · #Nuclear physics research studies #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #nucl-th
paper · pdf · doi:10.1088/0954-3899/29/4/302
published as J.Phys.G29:603-624,2003 · 25 pages (IOP style), 5 figures, revised manuscript accepted for publication in JPG
arxiv created 2003/02/14 · openalex publication_date 2003/02/21 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
The dilepton production in elementary pp → e + e − X reactions at BEVALAC energies T lab = 1–5 GeV is investigated. The calculations include direct e + e − decays of the vector mesons ρ 0 , ω and ϕ, Dalitz decays of the π 0 -, η-, ρ-, ω- and ϕ-mesons and of the baryon resonances Δ(1232), N (1520),.... The subthreshold vector meson production cross sections in pp collisions are treated in a way sufficient to avoid double counting with the inclusive vector meson production. The vector meson dominance model for the transition form factors of the resonance Dalitz decays R → e + e − N is used in an extended form to ensure correct asymptotics which are in agreement with the quark counting rules. Such a modification gives a unified and consistent description of both R → N γ radiative decays and R → N ρ(ω) meson decays. The effect of multiple pion production on the experimental efficiency for the detection of the dilepton pairs is studied. We find the dilepton yield in reasonable agreement with the experimental data for the set of intermediate energies whereas at the highest energy T lab = 4.88 GeV, the number of dilepton pairs is likely to be overestimated experimentally in the mass range M = 300–700 MeV.