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Recent X-ray observations of intense high-speed outflows in quasars suggest that supercritical accretion on to the central black hole may have an important effect on a host galaxy. I revisit some ideas of Silk and Rees, and assume such flows occur in the final stages of building up the black hole mass. It is now possible to model explicitly the interaction between the outflow and the host galaxy. This is found to resemble a momentum-driven stellar wind bubble, implying a relation M_BH = (f_g kappa/2 pi G^2) sigma^4 = 1.5 10^8 sigma_200^4 Msun between black hole mass and bulge velocity dispersion (f_g = gas fraction of total matter density, kappa = electron scattering opacity), without free parameters. This is remarkably close to the observed relation in both slope and normalization. This result suggests that the central black holes in galaxies gain most of their mass in phases of super-Eddington accretion, which are presumably obscured or at high redshift. Observed super-Eddington quasars are apparently late in growing their black hole masses.
For galaxies hosting supermassive black holes (SMBHs), it has been observed that the mass of the central black hole (M_BH) tightly correlates with the effective or central velocity dispersion (sigma) of the host galaxy. The origin of this M_BH - sigm
We have studied the location of narrow-line Seyfert 1 (NLS1) galaxies and broad-line Seyfert 1 (BLS1) galaxies on the M_BH - sigma relation of non-active galaxies. We find that NLS1 galaxies as a class - as well as the BLS1 galaxies of our comparison
We utilize the local velocity dispersion function (VDF) of spheroids, together with their inferred age--distributions, to predict the VDF at higher redshifts (0<z<6), under the assumption that (i) most of the stars in each nearby spheroid formed in a
Stationary solutions of 5D supergravity with U(1) isometry can be efficiently studied by dimensional reduction to three dimensions, where they reduce to solutions to a locally supersymmetric non-linear sigma model. We generalize this procedure to 5D
We use hydrodynamical simulations to study the color transformations induced by star formation and active galactic nuclei (AGN) during major mergers of spiral galaxies. Our modeling accounts for radiative cooling, star formation, and supernova feedba