相关论文: Dynamical Structure of Viscous Accretion Disks wit…

We explore self-similar hydrodynamic evolution of central voids embedded in an isothermal gas of spherical symmetry under the self-gravity. More specifically, we study voids expanding at constant radial speeds in an isothermal gas and…

The local stability of accretion disks with advection is studied together with the considerations of radial viscous force and thermal diffusion. For a geometrically thin, radiative cooling dominated disk, the thermal diffusion has nearly no…

We use the mean-field dynamo equations to show that an incoherent alpha effect in mirror-symmetric turbulence in a shearing flow can generate a large scale, coherent magnetic field. We illustrate this effect with simulations of a few simple…

Standard, planar accretion discs operate through a dissipative mechanism, usually thought to be turbulent, and often modelled as a viscosity. This acts to take energy from the radial shear, enabling the flow of mass and angular momentum in…

For the first time, {\it all} available pseudo-Schwarzschild potentials are exhaustively used to investigate the possibility of shock formation in hydrodynamic, invicid, black hole accretion discs. It is shown that a significant region of…

We study the global accretion-ejection solutions around a rotating black hole considering three widely accepted pseudo-Kerr potentials that satisfactorily mimic the space-time geometry of rotating black holes. We find that all the pseudo…

As the luminosity of an accreting black hole drops to a few percent of Eddington, the spectrum switches from the familiar soft state to a hard state that is well-described by a distended and tenuous advection-dominated accretion flow…

Radial transport of particles, elements and fluid driven by internal stresses in three-dimensional (3D) astrophysical accretion disks is an important phenomenon, potentially relevant for the outward dust transport in protoplanetary disks,…

We examine the evolution and influence of viscosity-induced diskoseismic modes in simulated black hole accretion disks. Understanding the origin and behavior of such oscillations will help us to evaluate their potential role in producing…

We perform 3D radiation hydrodynamic local shearing box simulations to study the outcome of gravitational instability (GI) in optically thick Active Galactic Nuclei (AGN) accretion disks. GI develops when the Toomre parameter QT \leq 1, and…

We consider the effects of advection and radial gradients of pressure and radial drift velocity on the structure of accretion disks around black holes with proper description of optically thick/thin transitions. We concentrated our efforts…

Two significant progresses have been made in the past years on our understanding of hot accretion flows. One is that only a small fraction of accretion flow available at the outer boundary can finally falls onto the black hole while most of…

Context: Accretion onto galactic and supermassive black holes occurs in different modes, which are documented in hard and soft spectral states, commonly attributed to an advection-dominated flow (ADAF) inside a truncated disk and standard…

We investigate different accretion disk models and viscosity prescriptions in order to provide a basic explanation for the exotic temporal behavior in GRS 1915+105. Based on the fact that the overall cycle times are very much longer than…

We provide a 2.5-dimensional solution to a complete set of viscous hydrodynamical equations describing accretion-induced outflow and then plausible jet around black holes/compact objects. We prescribe a self-consistent advective…

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 investigate the global stability of a differentially rotating fluid shell threaded by vertical and azimuthal magnetic fields to linear, axisymmetric perturbations. This system, which models a thick accretion disk in the vicinity of its…

We suggest a model of the advection dominated accretion flow (ADAF) with magnetically driven outflows to explain hysteretic state transition observed in X-ray binaries (XRBs). The transition from a thin disk to an ADAF occurs when the mass…

The purpose of this paper is to explore the dynamical behaviour of hot accretion flow with thermal conduction. The importance of thermal conduction on hot accretion flow is confirmed by observations of the hot gas that surrounds Sgr A$^*$…

This paper studies the asymptotic stability of shock profiles and rarefaction waves under space-periodic perturbations for one-dimensional convex scalar viscous conservation laws. For the shock profile, we show that the solution approaches…