1D observed and best-fit spectra (gray and red curves, respectively) for the main mask apertures discussed in the main text (Section 4). The residuals between the observed and best-model spectra are shown as a black curve, while the green band encloses the ± 1σ uncertainties from the observations. Both the residuals and uncertainties are, in some cases, shifted arbitrarily to avoid confusion with the observed spectra. We note that the fit is performed only for (observed) wavelengths longer than 1.7 μm. The expected wavelengths of the main UV and optical lines are shown.