Quantum collective approach to the thermodynamic properties of degenerate plasma

Thermodynamic functions of a system of partially degenerate electrons and strongly coupled ions are derived from first principles. A quantum collective approach is developed to analyze nonidealities inherent to very high density plasma. The model considers the electron oscillations (plasmons) and ion oscillations (ion sound waves) as quasiparticles sharing the energy of the system. Statistical thermodynamic calculations lead to simple, analytical expressions for internal energy as well as an equation of state. A dispersion relation for the high frequency branch is introduced to take into account the partial degeneracy state and thereby to quantify temperature finiteness effect on thermodynamic properties of very dense plasma. The present results are in good quantitative agreement with the existing models and represent a significant improvement over previous calculations which are based mainly on numerical experiments. More physical insight is explicitly stated presently which makes a contribution to the theoretical knowledge of coupled degenerate plasma for thermonuclear fusion as well as of astrophysical interests