Collisionless Halos Around Black Holes
نویسنده
چکیده
When a black hole accretes slowly, the radiative cooling of the infalling gas is weak and the accretion disk does not form. A hot collisionless quasi-spherical halo is formed instead. The properties of such halos are discussed. The rate of accretion, the radiative efficiency, and the temperature and density near the hole are evaluated.
منابع مشابه
Formation of Supermassive Black Holes: Simulations in General Relativity
There is compelling evidence that supermassive black holes exist. Yet the origin of these objects, or their seeds, is still unknown. We discuss several plausible scenarios for forming the seeds of supermassive black holes. These include the catastrophic collapse of supermassive stars, the collapse of relativistic clusters of collisionless particles or stars, the gravothermal evolution of dense ...
متن کاملSe p 20 02 How black holes turn cusps into cores
Collapsing collisionless particle systems form gravitational bound halos with cuspy density profiles. Also hierarchical merging of these systems produce remnants with cuspy central density profiles. These results lead to the assumption of cuspy NFW [5] profiles for the density distribution in dark matter halos. However, observed rotation curves in disk galaxies suggest dark matter halos with is...
متن کاملRapid growth of high redshift black holes
We discuss a model for the early assembly of supermassive black holes (SMBHs) at the center of galaxies that trace their hierarchical build-up far up in the dark halo ‘merger tree’. Motivated by the observations of luminous quasars around redshift z ≈ 6 with SMBH masses ≈ 10M⊙, we assess the possibility of an early phase of stable super-critical quasi-spherical accretion in the BHs hosted by me...
متن کاملGravothermal collapse of self-interacting dark matter halos and the origin of massive black holes.
Black hole formation is an inevitable consequence of relativistic core collapse following the gravothermal catastrophe in self-interacting dark matter (SIDM) halos. Very massive SIDM halos form supermassive black holes (SMBHs) > or about 10(6)M(middle dot in circle) directly. Smaller halos believed to form by redshift z = 5 produce seed black holes of (10(2)-10(3))M(middle dot in circle) which ...
متن کاملThe Role of Primordial Kicks on Black Hole Merger Rates
Primordial stars are likely to be very massive ≥ 30 M⊙, form in isolation, and will likely leave black holes as remnants in the centers of their host dark matter halos in the mass range 10 − 10 M⊙. Such early black holes, at redshifts z∼ 10, could be the seed black holes for the many supermassive black holes found in galaxies in the local universe. If they exist, their mergers with nearby super...
متن کامل