1997/06/26 by G. Q. Li, G.Q. Li, G. E. Brown +1
Physics and Astronomy · #Baryon #Hadron #High-Energy Particle Collisions Research #Meson #Particle physics theoretical and experimental studies #Photon #Pulsars and Gravitational Waves Research #Radiative transfer #Spectral line #Thermal #hep-ph #nucl-ex #nucl-th
paper · pdf · doi:10.1016/s0375-9474(97)00808-7
published as Nucl.Phys. A632 (1998) 153-170 · RevTeX, 21 pages, including 13 postscript figures
arxiv created 1997/06/26 · openalex publication_date 1998/03/01 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Single photon spectra in heavy-ion collisions at SPS energies are studied in the relativistic transport model that incorporates self-consistently the change of hadron masses in dense matter. We separate the total photon spectrum into `background' arising from the radiative decays of π0 and η mesons, and the `themal' one from other sources. For the latter we include contributions from radiative decays of ρ, ω, η', and a1, radiative decays of baryon resonances, as well as two-body processes such as ππ→ ργ and πρ→ πγ. It is found that more than 95% of all photons come from the decays of π0 and η mesons, while the thermal photons account for less than 5% of the total photon yield. The thermal photon spectra in our calculations with either free or in-medium meson masses do not exceed the upper bound set by the experimental measurment of the WA80 Collaboration.