Abstract. We calculate the structure of accretion disk around a spinning black hole for accretion rates Ṁ = 0.01− 10M⊙ s−1. The model is fully relativistic and treats accurately the disk microphysics including neutrino emissivity, opacity, electron degeneracy, and nuclear composition. We find that the accretion flow always regulates itself to a mildly degenerate state with the protonto-nucleon ...

We re-derive the equation for vertical hydrodynamical equilibrium of stationary thin and slim accretion disks in the Kerr spacetime. All the previous derivations have been unsatisfactory, yielding unphysical singularities. Our equation is non-singular, more general, and simpler than those previously derived. Subject headings: accretion, accretion disks — black hole physics — hydrodynamics — rel...

Emission spectra of hot accretion disks characteristic of advection dominated accretion flow (ADAF) models are investigated for comparison with the brightest ultra-luminous source, X-1, in the galaxy M82. If the spectral state of the source is similar to the low luminosity hard state of stellar mass black holes in our Galaxy, a fit to the Chandra X-ray spectrum and constraints from the radio an...

We use the microlensing variability observed for nine gravitationally lensed quasars to show that the accretion disk size at 2500Å is related to the black hole mass by log(R2500/cm) = (15.6± 0.2) + (0.54± 0.28) log(MBH/10M⊙). This scaling is consistent with the expectation from thin disk theory (R ∝ M BH), but it implies that black holes radiate with relatively low efficiency, log(η) = −1.29 ± ...

Observations of the hot gas surrounding Sgr A* and a few other nearby galactic nuclei imply electron and proton mean free paths comparable to the gas capture radius: hot accretion likely proceeds under weakly-collisional conditions in these systems. As a result, thermal conduction, rather than convection, may be important on all scales and affect the global flow properties. The self-similar ADA...

Accretion disks are observed in young stars, cataclysmic variables, binary X-ray sources et al. Accretion disk theory was first developed as a theory with the local heat balance, where the whole energy produced by a viscous heating was emitted to the sides of the disk. Important part of this theory was the phenomenological treatment of the turbulent viscosity, known the “ alpha” prescription, w...

We self-consistently estimate the outflow rate from the accretion rates of an accretion disk around a black hole in which both the Keplerian and the sub-Keplerian matter flows simultaneously. While Keplerian matter supplies soft-photons, hot sub-Keplerian matter supplies thermal electrons. The temperature of the hot electrons is decided by the degree of inverse Comptonization of the soft photon...

Advection-dominated accretion flows (ADAFs) have a positive Bernoulli parameter, and are therefore gravitationally unbound. The Newtonian ADAF model has been generalized recently to obtain the ADIOS model that includes outflows of energy and angular momentum, thereby allowing accretion to proceed self-consistently. However, the utilization of a Newtonian gravitational potential limits the abili...

Abstract Theoretical models show that the power of relativistic jets active galactic nuclei depends on spin and mass central supermassive black holes, as well accretion. Here we report an analysis archival observations a sample blazars. We find significant correlation between jet kinetic holes. At same time, use multiple linear regression to analyze relationship accretion, spin, hole mass. hole...

Studies were made of ASCA spectra of seven ultra-luminous compact X-ray sources (ULXs) in nearby spiral galaxies; M33 X-8 (Takano et al. 1994), M81 X-6 (Fabbiano 1988b; Kohmura et al. 1994; Uno 1997), IC 342 Source 1 (Okada et al. 1998), Dwingeloo 1 X-1 (Reynolds et al. 1997), NGC 1313 Source B (Fabbiano & Trinchieri 1987; Petre et al. 1994), and two sources in NGC 4565 (Mizuno et al. 1999). Wi...