Fitting of the TPN spectra with ISL model spectrum. The upper panel is for the bright rim. The observed spectrum is shown as a histogram (thick black line). The upper and the lower continuous thin line in black show ISL model spectra for the bright rim and the sky positions, respectively. Their difference, the red continuous line, is the fit. The parameters used for the model spectrum were  mag and C₅₀₀₀ = 0.66. The residuals observation-minus-fit are shown as histogram (in red), shifted down by 20 units. The lower panel shows the core. Same as for the rim but the parameters used for the model fit were  mag and C₅₀₀₀ = 0.33.