Estimates of supermassive black hole (SMBH) spins for the standard accretion disk model: Comparison with relativistic fitting of SMBH spectra

In this study, we estimated the accretion rates onto supermassive black holes (SMBH) and their spins. Our results are based on the observed (rest frame) bolometric luminosities and the luminosities at λ=5100 Å, as well as virial estimates of black hole masses and scaling relations derived from the standard thin accretion disk model. We compared our results with black hole spin measurements derived by relativistic reflection fitting of SMBH X-ray spectra. The results obtained confirm our conclusion regarding the efficiency of deriving SMBH spin values based on the standard (Shakura-Sunyaev) accretion disk model. Polarimetric observations have a key role in determining the spin values.