相关论文: Highly Viscous Accretion Disks with Advection

By studying three-dimensional, radiative, global simulations of sub-Eddington, geometrically thin black hole accretion flows we show that thin disks which are dominated by magnetic pressure are stable against thermal instability. Such disks…

We examine the effect of thermal conduction on the observational properties of a super critical hot magnetized flow. We obtained self-similar solution of a magnetized disc when the thermal conduction plays an important role. Follow of our…

We examined the effect of toroidal magnetic fields on a viscous gaseous disk around a central object under an advection dominated stage. We found self-similar solutions for radial infall velocity, rotation velocity, sound speed, with…

Context. Evolution of massive stars is affected by a significant loss of mass either via (nearly) spherically symmetric stellar winds or by aspherical mass-loss mechanisms, namely the outflowing equatorial disks. However, the scenario that…

We investigate the time evolution of luminous accretion disks around black holes, conducting the two-dimensional radiation-hydrodynamic simulations. We adopt the alpha prescription for the viscosity. The radial-azimuthal component of…

An effect of stimulated radiation processes on thermal radiation from an accretion disk is considered. The radial density waves triggering flare emission and producing quasi-periodic oscillations in radiation from an accretion disk are…

We describe new optically thin solutions for rotating accretion flows around black holes and neutron stars. These solutions are advection dominated, so that most of the viscously dissipated energy is advected radially with the flow. We…

Accretion onto a compact object must occur through a disc when the material has some initial angular momentum. Thin discs and the thicker low radiative efficiency accretion flows are solutions to this problem that have been widely studied…

We explore conditions and structure of accretion disks in short-period Cata- clysmic Variables (CVs), which have evolved beyond the period minimum. We show that accretion discs in systems with extreme mass ratios grow up to the size of…

We consider the radial buoyancy of vertical magnetic field lines in radiation and gas pressure dominated accretion disks. We find that in addition to radial drift driven by turbulent diffusion and biased by the global field geometry, there…

We study energy flows in geometrically thick accretion discs, both optically thick and thin, using general relativistic, three-dimensional simulations of black hole accretion flows. We find that for non-rotating black holes the efficiency…

We investigated a semi-analytic and numerical model to study the geometrically thin and optically thick accretion disk around Maclaurin spheroid (MS). The main interest is in the inner region of the so called {\alpha}-disk, {\alpha} being…

Outflows and convective motions in accretion flows have been intensively discussed recently in the context of advection-dominated accretion flow (ADAF) based on two-dimensional (2D) and three-dimensional (3D) hydrodynamical simulations. We,…

Transitional disks are protoplanetary disk around young stars that display inner holes in the dust distribution within a few AU, which is accompanied nevertheless by some gas accretion onto the central star. These cavities could possibly be…

We construct an analytical black hole accretion disk model that incorporates both magnetic pressure and disk wind, which are found to be important from numerical simulations. A saturated magnetic pressure that relates the Alfven velocity…

We consider axisymmetric viscous accretion flows where a fraction f of the viscously dissipated energy is advected with the accreting gas as stored entropy and a fraction 1-f is radiated. When f is small (i.e. very little advection), our…

We examine highly super-Eddington black-hole models for SS 433, based on two-dimensional hydrodynamical calculations coupled with radiation transport. The super-Eddington accretion flow with a small viscosity parameter, $\alpha = 10^{-3}$,…

In this paper we explore numerically the evolution of a warped accretion disc. Here, we focus here on the regime where the warp evolves diffusively. By comparing the numerical results to a simple diffusion model, we are able to determine…

In low-mass disks, turbulent torques are probably the most important way of redistributing angular momentum. Here we present the theory of turbulent accretion disks. We show the molecular viscosity is far too small to account for the…

Millimeter sized dust grains experience radial velocities exceeding the gas velocities by orders of magnitude. The viscous evolution of the accretion disk adds disk material onto the central star's convective envelope, influencing its…