The influence of Coulomb interaction on the equation of state under nuclear statistical equilibrium conditions

In the domain of thermodynamic parameters characteristic of the initial collapse of iron stellar cores, we studied the influence of Coulomb interaction on the thermodynamic functions of a plasma under nuclear statistical equilibrium conditions. Our attention was focused on the nuclear component of the matter. We established that including the interaction shifts the equilibrium toward the nuclei with larger charges. However, this effect and the changes in thermodynamic quantities are noticeable only at high densities (ρ ? 10¹¹ g cm^?3), i.e., at an advanced stage of gravitational collapse. We also showed that the mean ion model is inadequate in regions with a coupling parameter Γ ～ 1. We point out a method for modifying the linear mixing model to properly pass to the Debye limit and discuss other multicomponent plasma models.