We show that the observational data of extragalactic radio sources tend to support the theoretical relationship between the jet precession period and the optical luminosity of the sources, as predicted by the model in which an accretion disk causes the central black hole to precess. Subject headings: accretion, accretion disks — black hole physics — galaxies: active — galaxies: jets

Central black hole masses for 118 spiral galaxies representing morphological stages S0/a through Sc and taken from the large spectroscopic survey of Ho et al. (1997) are derived using K s-band data from 2MASS. Black hole masses are found using a calibrated black-hole – K s bulge luminosity relation, while bulge lumi-nosities are measured by means of a two-dimensional bulge/disk decomposition ro...

We construct a model for black hole formation in galactic bulges. The initial state is a slowly rotating isothermal sphere, with an effective transport speed and rotation rate Q. The black hole mass is determined when the aeff centrifugal radius of the collapse flow exceeds the capture radius of the central black hole. This model reproduces the observed correlation between black hole masses and...

We present a high-resolution (R ≈ 16, 000) spectrum and a narrow-band image centered on the [Ne ]12.8 µm line of the central kpc region of the starburst/Seyfert 2 galaxy NGC 7582. The galaxy has a rotating circum-nuclear starburst disk, shown at great detail at a diffraction-limited resolution of 0. ′′ 4 (≈ 40 pc). The high spatial resolution allows us to probe the dynamics of the [Ne ] gas...

We analyze both experimentally and theoretically the physical mechanisms that determine the optical transmission through deep sub-wavelength bull's eye structures (concentric annular grooves surrounding a circular hole). Our analysis focus on the transmission resonance as a function of the distance between the central hole and its nearest groove. We find that, for that resonance, each groove be...

A significant fraction of local galaxies show evidence of nuclear activity. I argue that the bulk of this activity, while energetically not remarkable, derives from accretion onto a central massive black hole. The statistics of nearby active galactic nuclei thus provide an effective probe of black hole demography. Consistent with the picture emerging from direct dynamical studies, the local cen...

We present the results of deep spectroscopy for the central region of the cluster lens SDSS J1004+4112 with the Subaru telescope. A secure detection of an emission line of the faint blue stellar object (component E) near the center of the brightest cluster galaxy (G1) confirms that it is the central fifth image of the lensed quasar system. In addition, we measure the stellar velocity dispersion...

We investigate the recently proposed Kerr/CFT correspondence in the context of heterotic string theory. The Kerr/CFT correspondence states that the near-horizon states of an extremal four (or higher) dimensional black hole could be identified with a certain chiral conformal field theory under the conjecture that the central charges from the non-gravitational fields vanish. The corresponding Vir...

We consider the shape of an accretion disc whose outer regions are misaligned with the spin axis of a central black hole and calculate the steady state form of the warped disc in the case where the viscosity and surface densities are power laws in the distance from the central black hole. We discuss the shape of the resulting disc in both the frame of the black hole and that of the outer disc. ...

We make use of two empirical relations between the black hole mass and the global properties (bulge luminosity and stellar velocity dispersion) of nearby elliptical galaxies, to infer the mass of the central black hole (MBH) in low redshift radiogalaxies. Using the most recent determinations of black hole masses for inactive early type galaxies we show that the bulge luminosity and the central ...