Photon production through A1 resonance in high-energy heavy-ion collisions

Electromagnetic radiation from excited hadronic matter is one of the best ways to study the properties of matter. Considering various processes in the hadronic gas, Kapusta, Lichard, and Seibert have found a reaction with an intermediate virtual or to be the main source of photons with energy greater than 0.7 GeV. However, at temperatures considered, T=100-200 MeV, a pair can easily form an A1(1260) resonance, and we show that this mechanism leads to photon production rates exceeding those suggested previously.