Equation of State of H2-He mixtures for Precompressed Shock Experiments.

An H2-He equation of state (EOS) seeks to explain the most fundamental and simple binary molecular systems. An accurate H2:He EOS at high pressures and temperatures is necessary to explain structural and evolutionary models of gas giant planets. Precompressed shock experiments achieve the necessary conditions to test such models, however accuracy to within 1% is required. In this study we use Brillouin spectroscopy to derive a highly accurate static density-pressure equation of state of 1:1 and 9:1 H2:He mixtures from 0.5-5.4 GPa. We then compare our derived EOS ideal mixing models and computational studies performed.