Dynamical thermalization in heavy-ion collisions

Ultrarelativistic heavy-ion collisions at the Relativistic Heavy-Ion Collider (RHIC) and the Large Hadron Collider (LHC) provide a hot and ultra-dense form of matter composed of deconfined quarks and gluons, named Quark-Gluon Plasma (QGP). Different models like EPOS and PHSD allow the study of the space-time evolution of such heavy-ion collisions. Their dynamics is complicated; hence, various stages should be considered. The first is the primary scattering which defines to a large extent the matter distribution in the phase-space. The second stage concerns the evolution of the partonic system until the system is sufficiently dilute to hadronise. The EPOSi+PHSDe approach is introduced in this thesis, in which the EPOS model is used to determine the initial distribution of matter (partons/hadrons). This part is referred to as EPOSi. Then PHSD is employed to simulate the evolution of the matter in a non-equilibrium transport approach, referred to as PHSDe. The coupling of the two approaches is non-trivial and not straight-forward, and is discussed in detail in this manuscript. Comparing the three models, EPOS, EPOSi+PHSDe, and PHSD, interesting results find concerning their respective space-time evolutions. The results demonstrate considerably different behavior in terms of radial expansion, especially asymmetric expansion, indicating that these three models will provide different results concerning key observables. To confirm this, we study the 'bulk matter observables' (p_T/m_T spectra, y/η distribution, v_2/3/4) for Au-Au collisions at 200 GeV/A. We also investigate the Electromagnetic probes compared to the PHSD approach. (author)