Results of the chi-square test applied to our observations and the non-LTE model grid of the S(0) to S(7) H₂ lines integrated intensities (see Eq. (8)). Each panel of the mosaic corresponds to the panels shown in Fig. 9 (positions indicated in Fig. 3). The term Γ is the power-law index, and N_tot is the total column density for T > T_min = 25 K (see Eqs. (6) and (7)). The background color indicates the absolute value of χ², and the set of black contours indicate the inner areas corresponding to the 1σ, 2σ, and 3σ levels, that is, ${\chi }^2\le \left[1.17{\chi }_{\text{min}}^2,1.67{\chi }_{\text{min}}^2,2.5{\chi }_{\text{min}}^2\right]$, where ${\chi }_{\min }^2$ is the minimum value of χ² across the model grid $(\text{Δ}{\chi }^2(n\sigma )=[1+n/(N-p)]{\chi }_{\min }^2$ where σ is the measurement error, N is the number of measurements, and p is the number of fit parameters).