DOE OSTI2016
We investigate the correlations between the black hole (BH) mass M{sub BH}, the velocity dispersion σ, the bulge mass M{sub Bu}, the bulge average spherical density ρ{sub h}, and its spherical half-mass radius r{sub h}, constructing a database of 97 galaxies (31 core ellipticals, 17 power-law ellipticals, 30 classical bulges, and 19 pseudobulges) by joining 72 galaxies from the literature to 25 galaxies observed during our recent SINFONI BH survey. For the first time we discuss the full error covariance matrix. We analyze the well-known M{sub BH}–σ and M{sub BH}–M{sub Bu} relations and establish the existence of statistically significant correlations between M{sub Bu} and r{sub h} and anticorrelations between M{sub Bu} and ρ{sub h}. We establish five significant bivariate correlations (M{sub BH}–σ–ρ{sub h}, M{sub BH}–σ–r{sub h}, M{sub BH}–M{sub Bu}–σ, M{sub BH}–M{sub Bu}–ρ{sub h}, M{sub BH}–M{sub Bu}–r{sub h}) that predict M{sub BH} of 77 core and power-law ellipticals and classical bulges with measured and intrinsic scatter as small as ≈0.36 dex and ≈0.33 dex, respectively, or 0.26 dex when the subsample of 45 galaxies defined by Kormendy and Ho is considered. In contrast, pseudobulges have systematically lower M{sub BH} but approach the predictions of all of the above relations at spherical densities ρ{sub h}⩾10{sup 10} M{sub ⊙} kpc{sup −3} or scale lengths r{sub h}⩽1 kpc. These findings fit in a scenario of coevolution of BH and classical-bulge masses, where core ellipticals are the product of dry mergers of power-law bulges and power-law ellipticals and bulges the result of (early) gas-rich mergers and of disk galaxies. In contrast, the (secular) growth of BHs is decoupled from the growth of their pseudobulge hosts, except when (gas) densities are high enough to trigger the feedback mechanism responsible for the existence of the correlations between M{sub BH} and galaxy structural parameters.
79 ASTRONOMY AND ASTROPHYSICS↗