Plasma equation of state accounting for ion core volume

Equation of state for gaseous plasma is well described by the Saha model. In the present paper, we include accounting for finite ion core volumes into this model. This improvement allows to expand the Saha model on superhigh densities and moderate temperatures where plasma can be considered liquid. In this domain, thermodynamics of the Saha model is essentially close to the one of the Tomas-Fermi model which is conventionally used for condensed matter. To construct wide-range equation of state, we imply interpolation of the two mentioned models providing rigorous thermodynamic consistency. Comparison with experimental data on shock adiabats shows good agreement for a very wide range of pressures.