Collision energy dependence of elliptic flow of identified hadrons in heavy-ion collisions using the PHSD model

Abstract

We report the first predictions of elliptic flow ($v_2$) of identified hadrons at mid-rapidity ($|y| <$ 1.0) in Au+Au collisions at $E_{lab} =$ 6.7, 8, 11, and 25 A GeV using the Parton Hadron String Dynamics (PHSD) model. The transverse momentum ($p_\mathrm{T}$) dependence of identified hadron $v_2$ in different centrality intervals (0-10%, 10-40%, and 40-80%) are shown. A clear centrality dependence of $v_2(p_\mathrm{T})$ is observed for particles at $E_{lab} = $ 25 and 11 A GeV, while the centrality dependence becomes weaker for particles at $E_{lab} = $ 8 and 6.7 A GeV. Within the PHSD model, the number of constituent quark (NCQ) scaling of $v_2$ approximately follows in Au+Au collisions at all beam energies. A collision energy ($\sqrt{s_{NN}}$) dependence of $\pi$, $K$, and $p$ $v_2$ is studied in comparison with available published experimental data in the beam energy range of 6-25 A GeV. These predictions will help in interpreting the data from the forthcoming Compressed Baryonic Matter (CBM) experiment at the Facility for Antiproton and Ion Research (FAIR) and Multi-Purpose Detector (MPD) at the Nuclotron-based Ion Collider facility (NICA).