Authors: Nandini Sahu, Alister W. Graham, Benjamin L. Davis
Analyzing a sample of 84 early-type galaxies with directly-measured super-massive black hole masses — nearly doubling the sample size of such galaxies with multi-component decompositions — a symmetric linear regression on the reduced (merger-free) sample of 76 galaxies reveals MBH ∝(M*,sph)1.27±0.07 with a total scatter of Δrms=0.52 dex in the log(MBH) direction. However, and importantly, we discover that the ES/S0-type galaxies with disks are offset from the E-type galaxies by more than a factor of ten in their MBH/M*,sph ratio, with ramifications for formation theories, simulations, and some virial factor measurements used to convert AGN virial masses into MBH. Separately, each population follows a steeper relation with slopes of 1.86±0.20 and 1.90±0.20, respectively. The offset mass ratio is mainly due to the exclusion of the disk mass, with the two populations offset by only a factor of two in their MBH/M*,gal ratio in the MBH-M*,gal diagram where MBH ∝(M*,gal)1.8±0.2 and Δrms=0.6±0.1 dex depending on the sample. For MBH > 107 MSun, we detect no significant bend nor offset in either the MBH-M*,sph or MBH-M*,gal relations due to barred versus non-barred, or core-Sérsic versus Sérsic, early-type galaxies. For reference, the ensemble of late-type galaxies (which invariably are Sérsic galaxies) follow MBH-M*,sph and MBH-M*,gal relations with slopes equal to 2.16±0.32 and 3.05±0.70, respectively. Finally, we provide some useful conversion coefficients, υ, accounting for the different stellar mass-to-light ratios used in the literature, and we report the discovery of a local, compact massive spheroid in NGC 5252.