Dense gas effects in the Rayleigh-Brillouin scattering spectra of SF6

Rayleigh-Brillouin scattering spectra of SF6 are modeled at room temperature in the pressure range [0.2–5] bar and compared to recent experimental measurements (Wang et al., 2017). It is shown that lineshape models that account for density-dependent corrections to the thermodynamic properties provide substantially better agreement than the models assuming an ideal gas model. For intermediate pressures, where a hydrodynamic description of the spectra fails due to kinetic effects, the Enskog-Vlasov kinetic model is shown to reproduce experimental data with good accuracy both at low and high pressure.