相关论文: A new hydrodynamic spherical accretion exact solut…
A new class of accelerating, exact, explicit and simple solutions of relativistic hydrodynamics is presented. Since these new solutions yield a finite rapidity distribution, they lead to an advanced estimate of the initial energy density…
Nekrasov's integral equation describing water waves of permanent form, determines the angle phi that the wave surface makes with the horizontal. The independent variable s is a suitably scaled velocity potential, evaluated at the free…
The rate of turbulent spherical accretion onto a compact object might be much smaller than the Bondi rate. It is suggested that the rate of accretion onto Sgr A-star is much smaller than the Bondi rate.
We present high-resolution, three-dimensional hydrodynamic simulations of the fueling of supermassive black holes in elliptical galaxies from a turbulent medium on galactic scales, taking M87* as a typical case. The simulations use a new…
Stokes perturbative solution of the nonlinear (boundary value dependent) surface gravity wave problem is known to provide results of reasonable accuracy to engineers in estimating the phase speed and amplitudes of such nonlinear waves. The…
Hot gas around a supermassive black hole (SMBH) should be captured within the gravitational "sphere of influence", characterized by the Bondi radius. Deep Chandra observations have spatially resolved the Bondi radii of five nearby SMBHs…
(accepted for publication in the Ap.J.) I present a general classification of self-similar solutions to the equations of gravitational hydrodynamics that contain many previous results as special cases. For cold flows with spherical…
An explicit necessary condition for the occurrence of resonance scattering of axial gravitational waves, along with the internal trapping of null geodesics, is proposed for static spherically symmetric perfect fluid solutions to Einstein's…
In this article, a special static spherically symmetric perfect fluid solution of Einstein's equations is provided. Though pressure and density both diverge at the origin, their ratio remains constant. The solution presented here fails to…
Black holes (BHs) are believed to be a key ingredient of galaxy formation. However, the galaxy-BH interplay is challenging to study due to the large dynamical range and complex physics involved. As a consequence, hydrodynamical cosmological…
We perform one-dimensional radiation hydrodynamical simulations to solve accretion flows onto massive black holes (BHs) with a very high rate. Assuming that photon trapping limits the luminosity emerging from the central region to…
We present new, exact, finite solutions of relativistic hydrodynamics for longitudinally expanding fireballs for arbitrary constant value of the speed of sound. These new solutions generalize earlier, longitudinally finite, exact solutions,…
We carry out 2D viscous hydrodynamics simulations of circumbinary disk (CBD) accretion using {\footnotesize AREPO}. We resolve the accretion flow from a large-scale CBD down to the streamers and disks around individual binary components.…
Static spherically symmetric solutions to the Einstein-Euler equations with prescribed central densities are known to exist, be unique and smooth for reasonable equations of state. Some criteria are also available to decide whether…
We present a numerical method for spatially 1.5-dimensional and time-dependent studies of accretion disks around black holes, that is originated from a combination of the standard pseudo-spectral method and the adaptive domain decomposition…
The commonly applied self-similar solution of the problem of the converging shock wave (shock) evolution with constant compression of the medium behind the shock front results in an unlimited increase of the medium velocity in the vicinity…
The accretion of hot slowly rotating gas onto a supermassive black hole is considered. Rotation velocities at the Bondi radius r_B are small in comparison with speed of sound c_s. The centrifugal barrier at a depth r_c = l^2/G M_BH << r_B…
The general relativistic accretion onto a black hole is investigated in which the motion is steady and spherically symmetrical, the gas being at rest at infinity. Two models with different equations of state are compared. Numerical…
We analyze 134 ks Chandra ACIS-I observations of the Galactic Centre (GC) performed in July 2011. The X-ray image with the field of view $17' \times 17'$ contains the hot plasma surrounding the Sgr~A*. The obtained surface brightness map…
We present the first results from two-dimensional simulations of radiatively-efficient accretion of metal-free gas onto intermediate-mass black holes. We fix the shape of the spectral energy distribution of the radiation produced near the…