Infrared versus CO(1–0) luminosity. Bottom: aperture-corrected CO(1–0) luminosity () versus infrared luminosity (L_IR) for the Seyfert 2 galaxies (red diamonds). The best-fit parameters (α = 0.93 ± 0.13, β = 0.90 ± 0.07) were obtained with an MCMC regression analysis and are represented by the solid black line, and the light blue area covers the parameter space between the 16th and 84th percentile. The relation for SFGs from the literature is reported as dotted (Sargent et al. 2014) and dot-dashed (Genzel et al. 2010) lines. The control sample is shown with gray circles (DustPedia) and green squares (Co19). Top: ratio as a function of L_IR. The horizontal dashed gray line is the median value.