Comparison of the Rayleigh-Brillouin spectrum of He, Ne, and Ar with a generalized Enskog theory

The generalized Enskog model solution of Furtado et al. for the Brillouin spectrum $S(q,\omega )$ is compared with the experimental results for compressed He, Ne, and Ar. A discrepancy between the two which localizes around the Brillouin component at high densities is found. It is also noted that the calculated spectrum disagrees with the equivalent curve for pure hydrodynamics at high densities and with an equivalent-model solution of the Boltzmann equation at low densities.