Examples of close pairs of galaxies, at different redshifts and with various mass ratios in the UDF-Mosaic field. From left to right: HST image in the F775W filter with the redshift of the primary galaxy, MUSE reconstructed white light image, narrow-band image of one of the brightest emission lines of the pair, and the zoomed spectra of the two galaxies around this line (red for the primary galaxy and blue for its companion) with the labeled MUSE ID, mass ratio, relative velocity difference, and projected separation distance. Images are 10″ in linear size and centered around the primary galaxy, circled in white. The green circle indicates the location of its companion. The first two close pairs correspond to the very minor and minor regimes, and the last two are major close pairs at low and high redshift.