Directed flow in relativistic heavy-ion collisions within the PHSD transport approach and 3FD hydrodynamical model

Hot Quarks 2014: Workshop for young scientists on the physics of ultrarelativistic nucleus-nucleus collisions

Konchakovski, V.P.^1 ; Cassing, W.^1 ; Ivanov, Y.B.^2,3 ; Toneev, V.D.^4

Institute for Theoretical Physics, University of Giessen, Giessen

35392, Germany^1

Kurchatov Institute, Moscow

123098, Russia^2

National Research Nuclear University MEPhI, Moscow

115409, Russia^3

Joint Institute for Nuclear Research, Dubna

141980, Russia^4

关键词: Beam energies;    Charged pions;    Hydrodynamical model;    Inverse process;    Model results;    Pair creation;    Relativistic heavy ion collision;    Transport modeling;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/612/1/012055/pdf
DOI  :  10.1088/1742-6596/612/1/012055

来源: IOP

【 摘 要 】

We analyze recent STAR data for the directed flow of protons, antiprotons and charged pions obtained within the beam energy scan program within the Parton-Hadron-String- Dynamics (PHSD) transport model and the 3-Fluid hydroDynamics (3FD) approach. We clarify the role of partonic degrees of freedom in the kinetic PHSD approach. 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 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 pp¯ annihilation and the inverse processes for Np¯pair creation from multi-meson interactions. Generally, a semi-qualitative agreement between the measured data and model results supports the idea of a crossover type quark-hadron transition which softens the nuclear EoS.