Black Holes of Active and Quiescent Galaxies. I. The Black Hole–Bulge Relation Revisited

Massive Black Holes detected in the centers of many nearby galaxies show anapproximately linear relation with the luminosity of the host bulge, with theblack hole mass being 0.001-0.002 of the bulge mass. Previous work suggestedthat black holes of active (Seyfert 1) galaxies follow a similar relation, butapparently with a significantly lower value of $M_{\rm BH}/M_{\rm bulge}$(Wandel 1999). New data show that this difference was mainly due tooverestimating the black hole mass in quiescent galaxies and overestimating thebulge magnitude of Seyfert galaxies. Using new and updated data we show thatAGNs (Seyfert galaxies and quasars) follow the same BH-bulge relation asordinary (inactive) galaxies. We derive the BH-bulge relation for a sample of55 AGNs and 35 quiescent galaxies, finding that broad line AGNs have an averageblack hole/bulge mass fraction of $\sim 0.0015$ with a strong correlation (Mbh~ Lbulge^{0.9\pm 0.16}). This BH-bulge relation is consistent with the BH-bulgerelation of quiescent galaxies and much tighter than previous results. Narrowline AGNs appear to have a lower ratio, Mbh/Mbulge ~ 10^{-4}-10^{-3}. We findthis to be a more general feature, the BH/bulge ratio in AGNs being inverselycorrelated with the emission-line width, implying a strong linear relationbetween the size of the broad emission line region and the luminosity of thebulge. Finally, combining AGNs with observed and estimated stellar velocitydispersion, we find a significant correlation (Mbh ~ v^{3.5-5}), consistentwith that of quiescent galaxies.Comment: 11 pages, 7 figures, accepted for publication in the Astrophysical Journal, submitted July 1