Spectra extracted from circular apertures (r = 0.6″) centred on the sources shown in the top-left insets. The shaded orange regions highlight the Hα+[N II] system associated with Arp220; the grey regions mark the channels with strong contamination caused by Na lasers. The vertical blue lines mark the brightest emission lines; in the bottom panel, Balmer and CaII absorption features around 3800 Å are marked with red lines. For each source, we report the spectroscopic redshift, the coordinates, and, for the sources in the DECaLS Survey (Dey et al. 2018), the optical magnitudes. The insets show the [O III] (for the first source) and [OII] emission maps for each source.