Effects of the momentum-dependent mean-field on collective flow in heavy-ion collisions at RHIC-STAR beam-energy scan energies

Au+Au collisions at √sNN = 3 and 4:5 GeV are simulated with the AMPT-HC transport model to examine how momentum-dependent nuclear interactions affect hadronic observables. Compared to the default momentum-independent potential, the momentum-dependent potential (MDI) suppresses Λ, π+, and K+ production and increases proton yields at larger absolute rapidities within 0.4 < pT < 2.0 GeV/c. The directed and elliptic flows of mesons appear to be more sensitive to MDI than those of baryons. This greater sensitivity may partly arise from MDI-induced changes in participant-spectator momentum exchange and the associated spectator-shadowing effects. The MDI effect on proton elliptic flow weakens systematically with increasing beam energy. These results indicate the importance of momentum-dependent interactions for describing collective flow at the collision energies investigated here.