Continuum-subtracted [CII] spectra (black histograms) as a function of the velocity offset computed with respect to the line peak. The figure shows three different galaxies with no detection of a broad component (left panel), and with individual outflow detection in the case of a single source (middle panel) and a possible merger (right panel). For each galaxy (whose name is reported at the top of the figure), the line profile is fitted with a single Gaussian function (in blue). A double (triple) Gaussian profile (in pink), that is the sum of one (green line) or two (green and grey lines) narrow and a broad (orange line) components, is also shown in the middle and right panels. The FWHM of both components and the corresponding reduced χ² are reported in each figure. For Mrk1089, FWHM_narrow is obtained from the Gaussian profile resulting from the sum of the two narrow components. The bottom panels display the residuals from the single (blue) and double/triple (pink) Gaussian functions. The dotted horizontal line marks the zero level, while the shaded area represents the rms of each spectrum at ±1σ. Flux densities and residuals are both normalized to the corresponding maximum values.