The hydrogen equation of state at high densities

TL;DR

This paper develops a comprehensive model for the high-density equation of state of hydrogen, integrating quantum and classical methods, and validates it against advanced simulations, aiding astrophysics and fusion research.

Contribution

Introduces a two-fluid model combining quantum Green's function and classical HNC techniques for accurate high-density hydrogen EOS calculations.

Findings

Model agrees with DFT-MD and quantum Monte Carlo results at high densities.

Provides thermodynamic properties across the entire density range.

Enables physical picture calculations for dense hydrogen.

Abstract

We use a two-fluid model combining the quantum Green's function technique for the electrons and a classical HNC description for the ions to calculate the high-density equation of state of hydrogen. This approach allows us to describe fully ionized plasmas of any electron degeneracy and any ionic coupling strength which are important for the modeling of a variety of astrophysical objects and inertial confinement fusion targets. We have also performed density functional molecular dynamics simulations (DFT-MD) and show that the data obtained agree with our approach in the high density limit. Good agreement is also found between DFT-MD and quantum Monte Carlo simulations. The thermodynamic properties of dense hydrogen can thus be obtained for the entire density range using only calculations in the physical picture.