α_OX vs. L_2500 Å for a compilation of AGN catalogs. Symbols refer to the AGN samples as in Fig. 4, except for the green dots, which are detected AGN with S/N > 5 from Lusso & Risaliti (2016). Upper limits for the HYPERION QSOs are estimated assuming a power law with fixed Γ = 2.4 (see Sect. 3 and Table 4). The dashed line is the linear fit from Martocchia et al. (2017) while the solid line refers to the best-fit relation from Lusso & Risaliti (2016) and for the subsample with S/N > 5, E(B − V)≥0.1, and 1.6 ≤ Γ_1 − 5 ≤ 2.8, with Γ_1 − 5 being the photon index estimated between the luminosities at 1 keV and 5 keV. Light blue crosses and asterisks present the values predicted by the QSOSED model (Kubota & Done 2018) assuming average HYPERION parameters and spin a = 0 and a = 1, respectively. These values are reported from top-left to bottom-right from log ṁ = −1 to log ṁ = 0.2 in steps of Δlog ṁ = 0.2.