IR luminosities as a function of CO(1−0) luminosities of our low-L_IR-selected SFGs (squares) compared to our compilation of galaxies with CO measurements from the literature (see Sect. 2.2). The color-coding of the various symbols refers to the J = 1, 2, and 3 CO transitions used to infer by applying the CO luminosity correction factors determined in Sect. 4. The best-fitting bisector linear relation to the entire sample of galaxies, , is plotted as a solid line. The z> 1 SFGs have on average a scatter in L_IR as large as 1 dex at a given value of and a 1σ dispersion of 0.38 dex in the y-direction about the best-fitting L_IR– relation.