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Related papers: MAD UFOs: Magnetically Arrested Discs with persist…

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In this letter, we investigate Bondi-like accretion flows with zero or low specific angular momentum by performing 3D general relativistic magnetohydrodynamic simulations. In order to check if relativistic jets can be launched magnetically…

High Energy Astrophysical Phenomena · Physics 2023-04-06 Tom M. Kwan , Lixin Dai , Alexander Tchekhovskoy

Active galactic nucleus (AGN) feedback is the process by which supermassive black holes in the centres of galaxies may moderate the growth of their hosts. Gas outflows from supermassive black holes release huge quantities of energy into the…

Black hole (BH) spin can play an important role in galaxy evolution by controlling the amount of energy and momentum ejected from near the BH into the surroundings. We focus on radiatively-inefficient and geometrically-thick…

High Energy Astrophysical Phenomena · Physics 2024-04-22 Beverly Lowell , Jonatan Jacquemin-Ide , Alexander Tchekhovskoy , Alex Duncan

We present the first-ever simulations of non-ideal magnetohydrodynamical (MHD) stellar winds coupled with disc-driven jets where the resistive and viscous accretion disc is self-consistently described. The transmagnetosonic, collimated MHD…

Astrophysics · Physics 2008-11-26 Fabien Casse , Zakaria Meliani , C. Sauty

We study the two-dimensional, time-dependent MHD of radiation-driven winds from luminous accretion disks initially threaded by a purely axial magnetic field. The radiation force is mediated primarily by spectral lines. We use ideal MHD to…

Astrophysics · Physics 2009-11-07 D. Proga

We present two-temperature, radiative general relativistic magnetohydrodynamic simulations of Magnetically Arrested Discs (MAD) that launch powerful relativistic jets. The mass accretion rates of our simulations are scaled to match the…

High Energy Astrophysical Phenomena · Physics 2019-04-11 Andrew Chael , Ramesh Narayan , Michael D. Johnson

Entangled magnetic fields entering into an accretion flow would very soon be stretched into a dominant toroidal component due to strong differentially rotating motion inside the accretion disc. This is particularly true for weakly viscous,…

High Energy Astrophysical Phenomena · Physics 2017-09-20 Arnab Deb , Kinsuk Giri , Sandip K. Chakrabarti

We study the effects of outflow/wind on the gravitational stability of accretion discs around supermassive black holes using a set of analytical steady-state solutions. Mass-loss rate by the outflow from the disc is assumed to be a…

Astrophysics · Physics 2008-12-18 Fazeleh Khajenabi

We discuss the results of three-dimensional magnetohydrodynamic simulations, using a pseudo-Newtonian potential, of thin disk (h/r ~ 0.1) accretion onto black holes. We find (i) that magnetic stresses persist within the marginally stable…

Astrophysics · Physics 2009-11-06 Christopher S. Reynolds , Philip J. Armitage , James Chiang

We present 3D adaptive mesh refinement MHD simulations of an isolated galaxy cluster that include injection of kinetic, thermal, and magnetic energy via a central active galactic nucleus (AGN) in order to study and evaluate the role that…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 P. M. Sutter , H. -Y. Yang , P. M. Ricker , G. Foreman , D. Pugmire

We report results from simulations in general relativity of magnetized disks accreting onto merging black hole binaries, starting from relaxed disk initial data. The simulations feature an effective, rapid radiative cooling scheme as a…

Ultraluminous X-ray sources (ULXs) have captivated researchers for decades due to their exceptionally high luminosities and unique spectral characteristics. Some of these sources defy expectations by exhibiting super-Eddington luminosities…

High Energy Astrophysical Phenomena · Physics 2025-05-07 Mayank Pathak , Banibrata Mukhopadhyay

Episodic ejection of plasma blobs have been observed in many black hole systems. While steady, continuous jets are believed to be associated with large-scale open magnetic fields, what causes the episodic ejection of blobs remains unclear.…

Astrophysics · Physics 2009-11-13 Feng Yuan , Jun Lin , Kinwah Wu , Luis C. Ho

Magnetic fields advected along with low angular momentum accretion flows predominantly become toroidal due to the strong azimuthal velocity close to a black hole. We study self-consistently the movements of these flux tubes inside an…

High Energy Astrophysical Phenomena · Physics 2020-01-15 Sudip K. Garain , Dinshaw S Balsara , Sandip K Chakrabarti , Jinho Kim

Recent work on the structure of magnetic fields in a turbulent medium gives predictions for the properties of the magnetic flux tubes as a function of the Mach number and scale of the turbulence, and the resistivity and viscosity of the…

Astrophysics · Physics 2010-04-23 Ethan T. Vishniac

Accretion disks are likely threaded by external vertical magnetic flux, which enhances the level of turbulence via the magnetorotational instability (MRI). Using shearing-box simulations, we find that such external magnetic flux also…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Xue-Ning Bai , James M. Stone

We report on simulations in general relativity of magnetized disks onto black hole binaries. We vary the binary mass ratio from 1:1 to 1:10 and evolve the systems when they orbit near the binary-disk decoupling radius. We compare (surface)…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Roman Gold , Vasileios Paschalidis , Zachariah B. Etienne , Stuart L. Shapiro , Harald P. Pfeiffer

The relation between the mass accretion rate onto the circumstellar disc and the rate of mass ejection by magnetically driven winds is investigated using three-dimensional magnetohydrodynamics simulations. Using a spherical cloud core with…

Solar and Stellar Astrophysics · Physics 2017-07-05 Yuko Matsushita , Masahiro N. Machida , Yuya Sakurai , Takashi Hosokawa

We present results of numerical simulation of inviscid thick accretion disks and wind flows around black holes. We use Smoothed Particle Hydrodynamics (SPH) technique for this purpose. Formation of thick disks are found to be preceded by…

Astrophysics · Physics 2009-10-22 Diego Molteni , G. Lanzafame , S. K. Chakrabarti

We carried out three-dimensional global resistive magnetohydrodynamic (MHD) simulations of the cooling instability in optically thin hot black hole accretion flows by assuming bremsstrahlung cooling. General relativistic effects are…

Astrophysics · Physics 2015-06-24 Mami Machida , Kenji Nakamura , Ryoji Matsumoto