Production of pairs of mesons, leptons and quarks in ultraperipheral ultrarelativistic heavy ion collisions

Abstract

The main goal of the dissertation is theoretical determination of the total and differential cross sections for the production of pairs of mesons, leptons and quarks in ultraperipheral ultrarelativistic heavy ion collisions. The Equivalent Photon Approximation (EPA) in the impact parameter space has been used as a theoretical tool for calculation of the reaction mechanism in the electromagnetic processes. We have presented the predictions in a reference to STAR, PHENIX and ALICE experimental data. We have focused on the calculations with inclusion of the realistic charge distribution in nucleus and we have shown the difference between results for the realistic nucleus charge form factor and that for the monopole form factor often used in the literature. We have studied several elementary cross sections for fusion and we have compared our parametrizations of γγ→X1X2 processes to existing word experimental data. Furthermore, we have calculated the cross section for photoproduction of single and double ρ0 mesons, the latter due to a double-scattering mechanism. Additionally, we have studied the ρ0→π+π−and ρ0ρ0 → π+π−π+π−decays. Finally, we have discussed in detail electromagnetic excitation of gold and lead nuclei by soft photons and as well as the emission of neutrons from decays of the excited nuclear system.