Building a testable shear viscosity across the QCD phase diagram

Current experiments at the Relativistic Heavy Ion Collider (RHIC) are probing finite baryon densities where the shear viscosity to enthalpy ratio ηT/w of the quark gluon plasma remains unknown. We use the hadron resonance gas (HRG) model with the most up-to-date hadron list to calculate ηT/w at low temperatures and at finite baryon densities ρB. We then match ηT/w to a quantum-chromodynamics-based shear viscosity calculation within the deconfined phase to create a table across {T,μB} for different crossover and critical point scenarios at a specified location. We find that these new ηT/w(T,μB) values would require initial conditions at significantly larger ρB, compared to ideal hydrodynamic trajectories, to reach the same freeze-out point.