Equation of state of strongly interacting system using PNJL-HRG hybrid model

The equation of state of a strongly interacting system under equilibrium conditions form the baseline upon which various possible scenarios in relativistic heavy-ion collision experiments are built. Many of these quantities have been obtained in the lattice QCD framework with reliable continuum extrapolations. Recently the Polyakov-Nambu-Jona-Lasinio model has been reparametrized to some extent to reproduce quantitatively the lattice QCD data. Though the agreement had been encouraging but there seemed to be two remaining issues because of which the agreement was not completely satisfactory. One issue was that the high temperature phase showed certain disagreements, possibly indicating the requirement of the NJL parametrizations. Secondly there were certain disagreements in the low temperature region, possibly due to the absence of effective hadronic degrees of freedom. Here we shall address the latter by introducing an interpolating function that switches between a hadronic model at low temperatures to a partonic model at higher temperatures