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 an approximately linear relation with the luminosity of the host bulge, implying that the black hole (BH) mass is 0.001-0.002 of the bulge. Previous work suggested that the black holes of active (Seyfert 1) galaxies have a similar relation, but apparently with a significantly lower value of M-BH/M-bulge (Wandel). New data show that this difference was mainly due to overestimated BH masses in quiescent galaxies and bulge magnitudes in Seyfert galaxies. Using new and updated data we show that active galactic nuclei (AGNs) have the same BH-bulge relation as ordinary (inactive) galaxies. We derive the BH-bulge relation for a sample of 55 AGNs (Seyfert 1 galaxies-quasars) and 35 quiescent galaxies, finding that broad-line AGNs have an average BH/bulge mass fraction of similar to0.0015 with a strong correlation (M-BH proportional toL(bulge)(0.9+/-0.16)). This BH-bulge relation is consistent with the BH-bulge relation of quiescent galaxies and much tighter than previous results. Narrow-line AGNs appear to have a lower ratio, M-BH/M-bulge similar to 10(-4) to 10(-3). We examine various explanations for this lower ratio. We find that the BH/bulge ratio in AGNs is inversely correlated with the emission-line width, implying a strong linear relation between the size of the broad emission-line region and the host bulge luminosity. Finally, combining AGNs with observed and estimated stellar velocity dispersion, we find a significant correlation (M-BH proportional to sigma(3.5-5)), consistent with that of quiescent galaxies.