Calculating QCD Phase Diagram Trajectories of Nuclear Collisions using a Semi-analytical Model

Department of Physics, East Carolina University, Greenville, NC 27858

Published online: 1 March 2023

Abstract

At low to moderate collision energies where the parton formation time τ_F is not small compared to the nuclear crossing time, the finite nuclear thickness significantly affects the energy density ϵ(t) and net conserved-charge densities such as the net-baryon density n_B(t) produced in heavy ion collisions. As a result, at low to moderate energies the trajectory in the QCD phase diagram is also affected by the finite nuclear thickness. Here, we first discuss our semi-analytical model and its results on ϵ(f), n_R(t), n_Q(t), and n_s(t) in central Au+Au collisions. We then compare the T(t), μ_B(t), μ_Q(t), and μ_S(t) extracted with the ideal gas equation of state (EoS) with quantum statistics to those extracted with a lattice QCD-based EoS. We also compare the T-μ_B trajectories with the RHIC chemical freezeout data. Finally, we discuss the effect of transverse flow on the trajectories.