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Related papers: Modelling MHD accretion-ejection - from the launch…

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Astrophysical jets are launched from strongly magnetized systems that host an accretion disk surrounding a central object. The origin of the magnetic field, which is a key component of the launching process, is still an open question. Here…

High Energy Astrophysical Phenomena · Physics 2023-06-28 Giancarlo Mattia , Christian Fendt

We study the H$\alpha$ emission from jets using two-dimensional axisymmetrical simulations. We compare the emission obtained from hydrodynamic (HD) simulations with that obtained from magnetohydrodynamics (MHD) simulations. The magnetic…

Astrophysics · Physics 2009-11-11 Fabio De Colle , Alejandro Raga

We present global magnetohydrodynamic (MHD) simulations of accretion disks with a strong toroidal magnetic field using an equation of state that fixes the gas thermal scale height. The disk forms from the inflow of a rotating magnetized gas…

High Energy Astrophysical Phenomena · Physics 2025-05-20 Minghao Guo , Eliot Quataert , Jonathan Squire , Philip F. Hopkins , James M. Stone

Short gamma-ray bursts originate when relativistic jets emerge from the remnants of binary neutron star mergers. Both the jet and the remnant are believed to be strongly magnetized, and the presence of magnetic fields is known to influence…

High Energy Astrophysical Phenomena · Physics 2024-11-01 Giancarlo Mattia , Luca Del Zanna , Andrea Pavan , Riccardo Ciolfi

We present three-dimensional (3-D) magnetohydrodynamical (MHD) simulations of radiatively inefficient accretion flow around black holes. General relativistic effects are simulated by using the pseudo-Newtonian potential. We start…

Astrophysics · Physics 2009-11-10 Yoshiaki Kato , Shin Mineshige , Kazunari Shibata

Observations are providing increasingly detailed quantitative information about the accretion flows that power such high energy systems as X-ray binaries and active galactic nuclei. Analytic models of such systems must rely on assumptions…

Astrophysics · Physics 2008-11-26 J. F. Hawley , J. -P. De Villiers

We use global magnetohydrodynamic simulations to study the influence of net vertical magnetic fields on the structure of geometrically thin ($H/r \approx 0.05$) accretion disks in the Newtonian limit. We consider initial mid-plane gas to…

High Energy Astrophysical Phenomena · Physics 2020-01-23 Bhupendra Mishra , Mitchell C. Begelman , Philip J. Armitage , Jacob B. Simon

We examine, parametrically, the interaction between the magnetosphere of a rotating, young stellar object (YSO) and a circumstellar accretion disk using 2.5-D (cylindrically symmetric) numerical magnetoydrodynamic simulations. The…

Astrophysics · Physics 2009-11-07 Sean Matt , Anthony Goodson , Robert Winglee , Karl-Heinz Bohm

Semi-analytical models of disk outflows have successfully described magnetically-driven, self-confined super-Alfv\'enic jets from near Keplerian accretion disks. These Jet Emitting Disks are possible for high levels of disk magnetization…

High Energy Astrophysical Phenomena · Physics 2019-10-16 J. Jacquemin-Ide , J. Ferreira , G. Lesur

We present a detailed three dimensional magnetohydrodynamic (MHD) simulation describing the inner region of a disk accreting onto a black hole. To avoid the technical complications of general relativity, the dynamics are treated in…

Astrophysics · Physics 2009-10-31 John F. Hawley , Julian H. Krolik

Turbulent magnetic diffusivity plays an important role for accretion disks and the launching of disk winds. We have implemented magnetic diffusivity, respective resistivity in the general relativistic MHD code HARM. This paper describes the…

High Energy Astrophysical Phenomena · Physics 2017-01-04 Qian Qian , Christian Fendt , Scott Noble , Matteo Bugli

The dynamics and structure of accretion disks, which accumulate the vertical magnetic field in the centers, are investigated using two- and three-dimensional MHD simulations. The central field can be built up to the equipartition level and…

Astrophysics · Physics 2009-11-13 Igor V. Igumenshchev

We investigate the evolution of a disk wind into a collimated jet under the influence of magnetic diffusivity, assuming that the turbulent pattern in the disk will also enter the disk corona and the jet. Using the ZEUS-3D code in the…

Astrophysics · Physics 2009-11-07 Christian Fendt , Miljenko Cemeljic

We present a global magnetohydrodynamic (MHD) three dimensional simulation of a nonradiative accretion flow originating in a pressure supported torus. The evolution is controlled by the magnetorotational instability which produces…

Astrophysics · Physics 2009-11-06 John F. Hawley , Steven A. Balbus , James M. Stone

The study of Magnetically Arrested Disks (MAD) attract strong interest in recent years, as these disk configurations were found to generate strong jets as observed in many accreting systems. Here, we present the results of 14 general…

High Energy Astrophysical Phenomena · Physics 2023-10-12 G. -Q. Zhang , D. Bégué , A. Pe'er , B. -B. Zhang

Recent numerical simulations of MHD jets from accretion disks are briefly reviewed with emphasis on the scaling law for jet speed and the role of magnetic reconnection in relation to time variability in accretion disks, jets, and flares. On…

Astrophysics · Physics 2007-05-23 Kazunari Shibata , Seiichiro Aoki

We have performed self-consistent 2.5-dimensional nonsteady MHD numerical simulations of jet formation as long as possible, including the dynamics of accretion disks. Although the previous nonsteady MHD simulations for astrophysical jets…

Astrophysics · Physics 2015-05-13 Ahmed Ibrahim , Kazunari Shibata

We present the first three-dimensional magnetohydrodynamic (MHD) simulations of a circumbinary disk surrounding an equal mass binary. The binary maintains a fixed circular orbit of separation $a$. As in previous hydrodynamical simulations,…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Ji-Ming Shi , Julian H. Krolik , Stephen H. Lubow , John F. Hawley

Gas falling into a black hole (BH) from large distances is unaware of BH spin direction, and misalignment between the accretion disc and BH spin is expected to be common. However, the physics of tilted discs (e.g., angular momentum…

High Energy Astrophysical Phenomena · Physics 2022-12-06 Matthew Liska , Casper Hesp , Alexander Tchekhovskoy , Adam Ingram , Michiel van der Klis , Sera Markoff

Using magnetohydrodynamic (MHD) adaptive mesh refinement simulations, we study the formation and early evolution of disk galaxies with a magnetized interstellar medium. For a $10^{10}$ \msun halo with initial NFW dark matter and gas…

Astrophysics · Physics 2009-04-17 Peng Wang , Tom Abel