Fig. 8

Comparisons in the spectra of spontaneous RBS between the experimental data (the solid line) from Ref. [25], the LBE (the dashed line) for polyatomic gas [80], and the rational extended thermodynamics with 14 moments (the dash-dotted line) by Ruggeri and Sugiyama [54]. The light is scattered from CO₂ when Kn=0.1114. Note that the frequency is normalized by 1.06 GHz, and the shown spectra are the convolution of S_s(Kn,f_s) and the Lorentzian function Lor(f_s) with the Full Width at Half Maximum being 210 MHz, i.e., \(Lor(f_{s})\propto 1/(f_{s}^{2}+9.8\times 10^{-3})\)