Bolometric luminosity as a function of the temperature for the soft (left panel) and hard (right panel) black-body components, in comparison with the older XMM-Newton observations as in G21 (in grey). For the soft component, three L − T laws are overplotted: L ∝ T⁴ for a thin disc (Shakura & Sunyaev 1973), L ∝ T² for an advection-dominated disc around a BH (Watarai et al. 2000), and L ∝ T⁻⁴ as observed for NGC 1313 X-2 (Robba et al. 2021). The bolometric luminosities are computed in the 0.01−100 keV range.