Related papers: The Event Horizon General Relativistic Magnetohydr…
We present Horizon, a new graphics processing unit (GPU)-accelerated code to solve the equations of general relativistic magnetohydrodynamics in a given spacetime. We evaluate the code in several test cases, including magnetized Riemann…
We present a general procedure to solve numerically the general relativistic magnetohydrodynamics (GRMHD) equations within the framework of the 3+1 formalism. The work reported here extends our previous investigation in general relativistic…
The Event Horizon Telescope (EHT) has mapped the central compact radio source of the elliptical galaxy M87 at 1.3 mm with unprecedented angular resolution. Here we consider the physical implications of the asymmetric ring seen in the 2017…
The profound comprehension of the evolution and phenomenology of an Active Galactic Nucleus requires an accurate exploration of the dynamics of the magnetized gaseous disk surrounding the massive black hole in the centre. Many numerical…
We present a new numerical implementation of the general-relativistic resistive magnetohydrodynamics (MHD) equations within the Whisky code. The numerical method adopted exploits the properties of implicit-explicit Runge-Kutta numerical…
Current state-of-the-art simulations of accretion flows onto black holes require a significant level of numerical sophistication, in order to allow the three-dimensional modelling of relativistic magnetised plasma in a regime of strong…
We introduce our newly developed two different, three dimensional magneto hydrodynamical codes in detail. One of our codes is written in the Newtonian limit (NMHD) and the other is in the fully general relativistic code (GRMHD). Both codes…
We describe some recent results on the evolution of accretion disks around black holes and neutron stars obtained in magnetohydrodynamic (MHD) simulations in general relativity (GR) with the inclusion of radiation (GRRMHD).
Black hole (BH) accretion flows and jets are dynamic hot relativistic magnetized plasma flows whose radiative opacity can significantly affect flow structure and behavior. We describe a numerical scheme, tests, and an astrophysically…
We have developed a new three-dimensional general relativistic magnetohydrodynamic (GRMHD) code, RAISHIN, using a conservative, high resolution shock-capturing scheme. The numerical fluxes are calculated using the Harten, Lax, & van Leer…
We model the structure and evolution of black hole accretion disks, and their neighboring regions, using numerical simulations. The numerics is governed by the equations of general relativistic magneto-hydrodynamics (GRMHD). In particular,…
Astrophysical plasmas in relativistic spacetimes, such as black hole accretion flows, are often weakly collisional and require kinetic modeling to capture non-local transport and particle acceleration. However, the extreme scale separation…
We present results of models of the physical space and parameters of the accretion disk of Sagittarius A*, as well as simulations of its emergent spectrum. This begins with HARM, a 2D general relativistic magneto-hydrodynamic (GRMHD) model,…
We investigate numerical convergence in simulations of magnetically arrested disks around spinning black holes. Using the general-relativistic magnetohydrodynamics code Athena++, we study the same system at four resolutions (up to an…
Interpretation of resolved polarized images of black holes by the Event Horizon Telescope (EHT) requires predictions of the polarized emission observable by an Earth-based instrument for a particular model of the black hole accretion…
Using the Event Horizon Telescope (EHT), the gravitationally lensed rings around the supermassive black holes (SMBHs) in Messier 87 (M87) and Sagittarius A* (Sgr A*) have now been successfully imaged at a resolution under 10 gravitational…
Many astrophysical systems of interest to numerical relativity-such as rapidly rotating stars, black hole accretion disks, and core-collapse supernovae-exhibit near-symmetries. These systems generally consist of a strongly gravitating…
The equations of general relativistic magnetohydrodynamics (GRMHD) have become the standard mathematical framework for modeling high-energy plasmas in curved spacetimes. However, the fragility of the primitive variable reconstruction…
The numerical study of relativistic magnetohydrodynamics (MHD) plays a crucial role in high-energy astrophysics, but unfortunately is computationally demanding, given the complex physics involved (high Lorentz factor flows, extreme…
We present a novel spectral solver for general relativistic magnetohydrodynamics on dynamical spacetimes. By combining a high order discontinuous spectral method on mapped Chebyshev Fourier grids, our scheme attains exponential convergence.…