Trends among the [CII] luminosity coming from the diffuse halo around merging systems, L^diff, and their integrated physical properties. Different colors refer to different apertures adopted to extract the emission from the merging galaxies, L^diff, i, with i = 1″ (orange border), FWHM-based (green border), and peak (pink border). In each panel, the filled green pentagons are the estimates obtained after applying the correction for the tails of the ALMA PSF (see text for discussion). The green solid line and shaded areas are respectively the linear fit and the associated error for these estimates. We also report the Spearman coefficient (ρ) of the analyzed relation. Left: L^diff is shown as a function of the [CII] luminosity coming from the galaxies, L^gal. The black dot-dashed line is the 1:1 relation. Middle and right: L^diff as a function of the total SFR and total M_⋆ of the merging systems (see Table 1). DC_873321 is highlighted in gray; see the main text for the discussion on this candidate.