Dilepton production in microscopic transport theory with in-medium ρ\rho-meson spectral function

Sep 24, 2020
29 pages
Published in:
  • Phys.Rev.C 102 (2021) 6, 064913
  • Published: Jan 1, 2021
e-Print:

Citations per year

202020212022202320241342
Abstract: (APS)
We use the microscopic Giessen Boltzmann-Uehling-Uhlenbeck (GiBUU) transport model to calculate dilepton (e+e−) production in heavy-ion collisions at SIS18 energies focusing on the effect of collisional broadening of the ρ meson. The collisional width of the ρ meson at finite temperature and baryon density in nuclear matter is calculated on the basis of the collision integral of the GiBUU model. A systematic comparison with HADES data on dilepton production in heavy-ion collisions is performed. The collisional broadening of the ρ improves the agreement between theory and experiment for the dilepton invariant-mass distributions near the ρ pole mass and for the excess radiation in Au+Au at 1.23AGeV. We furthermore show that some remaining underprediction of the experimental dilepton spectra in C+C at 1AGeV and Au+Au at 1.23AGeV at intermediate invariant masses 0.2–0.4 GeV can be accounted for by adjusting the pn bremsstrahlung cross section in a way to agree with the inclusive dilepton spectrum from dp collisions at 1.25AGeV.
Note:
  • Relevant result figures replaced, correcting small bug in pion propagation, Conclusions unchanged
  • Relativistic Nuclear Collisions
  • dilepton: production
  • dilepton: spectrum
  • heavy ion: scattering
  • baryon: density
  • mass: pole
  • transport theory
  • broadening
  • spectral representation
  • finite temperature