IR (8–1000 μm) versus CO(2−1) luminosities. The QSO2s in our sample are shown with same colors and symbols as in Fig. 2. The solid line is the relation (log L_IR = 1.05 log ) found for LIRGs and ULIRGs at z ≤ 0.1 and dusty star forming galaxies at z > 1 from Greve et al. (2014). The dashed lines indicate the correlation scatter, of 0.27 dex. The dot-dashed line is the fit of star-forming galaxies with z = 0–2 from Genzel et al. (2010). This relation (log L_FIR = 1.15 log ) has a scatter of 0.31 dex and it corresponds to CO(1−0) instead of CO(2−1), so we assume r₂₁ = 1 and use L_IR = 1.3 × L_FIR to estimate total IR luminosity as indicated in Genzel et al. (2010). Pink plus symbols are the PG quasars at z < 0.1 from Shangguan et al. (2020b), open diamonds the PUMA ULIRGs at z < 0.16 from Pereira-Santaella et al. (2021), and blue asterisks the QSO2s at z ∼ 0.1 from Jarvis et al. (2020). The APEX of J1010 is higher than the corresponding ALMA value because it includes two companion galaxies, it is lower in the case of J1100, equal for J1430, and for J1356 is an upper limit.