Elliptic Flow of Protons and Antiprotons in Au+Au Collisions at $\sqrt{s_{NN}}$ = 7.7--62.4 GeV within Alternative Scenarios of Three-Fluid Dynamics

Abstract

Analysis of elliptic flow of protons and antiprotons in Au+Au collisions is performed in a wide range of incident energies $\sqrt{s_{NN}}$ = 7.7--62.4 GeV. Simulations has been done within the three-fluid model employing a purely hadronic equation of state (EoS) and two versions of the EoS involving deconfinement transition: an EoS with the first-order phase transition and that with a smooth crossover transition. It is found that the proton data are reproduced approximately to the same extent within all of the scenarios, including the hadronic one, while the deconfinement scenarios look certainly preferable for the antiproton elliptic flow. The fact that difference between elliptic flows of protons and antiprotons decreases with the incident energy rise is a consequence of reducing baryon stopping rather than an onset of deconfinement.