English

Dileptons and Photons from Coarse-Grained Microscopic Dynamics and Hydrodynamics Compared to Experimental Data

Nuclear Theory 2009-11-07 v1

Abstract

We compute the radiation of dileptons and photons using relativistic hydrodynamics and a coarse-grained version of the microscopic event generator UrQMD, both of which provide a good description of the hadron spectra. The currently most accurate dilepton and photon emission rates from perturbative QCD and from experimentally-based hadronic calculations are used. Comparisons are made to data on central Pb-Pb and Pb-Au collisions taken at the CERN SPS at a beam energy of 158 A GeV. Both hydrodynamics and UrQMD provide very good descriptions of the photon transverse momentum spectrum measured between 1 and 4 GeV, but very slightly underestimate the low mass spectrum of e+e- pairs, even with greatly broadened rho and omega vector mesons.

Keywords

Cite

@article{arxiv.nucl-th/0210032,
  title  = {Dileptons and Photons from Coarse-Grained Microscopic Dynamics and Hydrodynamics Compared to Experimental Data},
  author = {Joseph Kapusta},
  journal= {arXiv preprint arXiv:nucl-th/0210032},
  year   = {2009}
}

Comments

4 pages, 10 figures, Quark Matter 2002 proceedings

R2 v1 2026-07-22T18:28:08.320Z