Stellar dynamics around black holes in galactic nuclei

Stellar Dynamics around Black Holes in Galactic Nuclei

We classify orbits of stars that are bound to central black holes in galactic nuclei. The stars move under the combined gravitational influences of the black hole and the central star cluster. Within the sphere of influence of the black hole, the orbital periods of the stars are much shorter than the periods of precession. We average over the orbital motion and end up with a simpler problem and...

Collisional dynamics around binary black holes in galactic centers

We follow the sinking of two massive black holes in a spherical stellar system. The massive particles become bound under the regime of dynamical friction. Once bound, the binary hardens by three body encounters with surrounding stars. Unlike other assumptions the massive system moves inside the core providing an enhanced supply of reaction partners for the hardening. These are the first results...

Supermassive Black Holes in Galactic Nuclei

We discuss the link between the observations of distant quasars and those of massive dark objects in the cores of many local galaxies. We show how the formation of early black holes gives rise to the luminosity function of high z quasars, while it imprints into their dark local relics a related shape of the mass-dispersion correlation. We propose that in its lower section the correlation slope ...

Supermassive Black Holes in Galactic Nuclei

We review the motivation and search for supermassive black holes (BHs) in galaxies. Energetic nuclear activity provides indirect but compelling evidence for BH engines. Ground-based dynamical searches for central dark objects are reviewed in Kormendy & Richstone (1995, ARA&A, 33, 581). Here we provide an update of results from the Hubble Space Telescope (HST). This has greatly accelerated the d...

Supermassive Black Holes in Active Galactic Nuclei