Speaker
Dr
Volodymyr Konchakovski
(Institute for Theoretical Physics, Giessen University)
Description
Recent STAR data for the directed flow v1 obtained within the beam energy scan (BES) program has been analyzed within the Parton-Hadron-String-Dynamics (PHSD) transport model and a 3-Fluid Hydrodynamics (3FD) approach. The kinetic PHSD approach has been used to clarify the role of partonic degrees of freedom. The PHSD results, simulating a partonic phase and its coexistence with a hadronic one, are roughly consistent with data. The hydrodynamic results are obtained for two equations of state (EoS), a pure hadronic EoS and an EoS with a crossover type transition. The latter case is favored by the STAR experimental data. Special attention is paid to the description of antiproton directed flow based on the balance of p-pbar annihilation and the inverse processes for p-pbar pair creation from multi-meson interactions. Generally, the semiqualitative agreement between the measured data and the model results supports the idea of a crossover type of quark-hadron transition that softens the nuclear EoS but shows no indication of a first-order phase transition.
Primary author
Dr
Volodymyr Konchakovski
(Institute for Theoretical Physics, Giessen University)
Co-authors
Viacheslav Toneev
(JINR, Dubna, Russia)
Wolfgang Cassing
(University of Giessen)
Yuri Ivanov
(Kurchatov Institute, Moscow, Russia)
