Identified Fe II troughs for outflow system S2. The histograms show the VLT/UVES spectra in velocity space, and the corresponding dashed curves show the modeled Gaussian for the absorption. The model is based on the 1278 Å transition, and its template with fixed centroid and width was scaled to match the depth of all other troughs. The lower-energy level of the transition and the wavelengths are given for each panel.