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Related papers: Modelling MHD accretion-ejection - episodic ejecti…

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We present steady-state calculations of self-similar magnetized accretion discs driving cold, adiabatic, non-relativistic jets. For the first time, both the magnetic torque due to the jets and a turbulent "viscous" torque are taken into…

Astrophysics · Physics 2007-05-23 Fabien Casse , Jonathan Ferreira

Stationary magnetohydrodynamic (MHD) outflows from a rotating, conducting Keplerian accretion disk threaded by B-field are investigated numerically by time-dependent, axisymmetric (2.5D) simulations using a Godunov-type code. A large class…

Rotating outflows from protostellar disks might trace extended magneto-hydrodynamic (MHD) disk winds (DWs), providing a solution to the angular momentum problem in disk accretion for star formation. In the jet system HH 212, a rotating…

Astrophysics of Galaxies · Physics 2021-02-10 Chin-Fei Lee , Benoit Tabone , Sylvie Cabrit , Claudio Codella , Linda Podio , Ferreira , J. , Jacquemin-Ide , J

A popular model for jet collimation is associated with the presence of a large-scale and predominantly toroidal magnetic field originating from the central engine (a star, a black hole, or an accretion disk). Besides the problem of how such…

Astrophysics · Physics 2009-11-07 Li-Xin Li

The effect of a magnetic field on the linear phase of the advective-acoustic instability is investigated, as a first step toward a magnetohydrodynamic (MHD) theory of the stationary accretion shock instability taking place during stellar…

Solar and Stellar Astrophysics · Physics 2014-11-20 Jerome Guilet , Thierry Foglizzo

We perform GR-MHD simulations of outflow launching from thin accretion disks. As in the non-relativistic case, resistivity is essential for the mass loading of the disk wind. We implemented resistivity in the ideal GR-MHD code HARM3D,…

High Energy Astrophysical Phenomena · Physics 2019-09-04 Christos Vourellis , Christian Fendt , Qian Qian , Scott Noble

(Abridged) Based on the rapidly increasing all-sky data of Faraday rotation measures and polarised synchrotron radiation, the Milky Way's magnetic field is now modelled with an unprecedented level of detail and complexity. We aim to…

Astrophysics of Galaxies · Physics 2015-06-17 Oliver Gressel , Detlef Elstner , Udo Ziegler

We briefly review recent developments in black hole accretion disk theory, emphasizing the vital role played by magnetohydrodynamic (MHD) stresses in transporting angular momentum. The apparent universality of accretion-related outflow…

Astrophysics · Physics 2009-06-23 Zdenka Kuncic , Geoffrey V. Bicknell

A spinning black hole accreting from a disk of strongly magnetized plasma via a magnetically arrested disk is known to produce an efficient electromagnetic jet powered by the black hole's spin energy. We present general relativistic…

High Energy Astrophysical Phenomena · Physics 2023-08-11 Angelo Ricarte , Ramesh Narayan , Brandon Curd

Magnetically arrested accretion disks (MADs) around a rapidly rotating black hole (BH) have been proposed as a model for jetted tidal disruption events (TDEs). However, the stream and disk interact strongly at times, and this will lead to…

High Energy Astrophysical Phenomena · Physics 2025-05-21 Brandon Curd , Richard Anantua , Hayley West , Joaquin Duran

The powerful narrow jets observed to emanate from many compact accreting objects may arise from the twisting of a magnetic field threading a differentially rotating accretion disk which acts to magnetically extract angular momentum and…

Astrophysics · Physics 2009-11-06 R. V. E. Lovelace , H. Li , G. V. Ustyugova , M. M. Romanova , S. A. Colgate

Protostellar jets and winds are probably driven magnetocentrifugally from the surface of accretion disks close to the central stellar objects. The exact launching conditions on the disk, such as the distributions of magnetic flux and mass…

Astrophysics · Physics 2009-11-06 Ruben Krasnopolsky , Zhi-Yun Li , Roger D. Blandford

Jets can facilitate the mass accretion onto the protostars in star formation. They are believed to be launched from accretion disks around the protostars by magneto-centrifugal force, as supported by the detections of rotation and magnetic…

Astrophysics of Galaxies · Physics 2022-03-30 Chin-Fei Lee , Zhi-Yun Li , Hsien Shang , Naomi Hirano

We review advances in the theoretical and computational studies of disk winds, jets and outflows including: the connection between accretion and jets, the launch of jets from magnetized disks, the coupled evolution of jets and disks, the…

Astrophysics · Physics 2007-05-23 Ralph E. Pudritz , Rachid Ouyed , Christian Fendt , Axel Brandenburg

We present 3D general relativistic magnetohydrodynamic(GRMHD) simulations of zero angular momentum accretion around a rapidly rotating black hole, modified by the presence of initially uniform magnetic fields. We consider serveral angles…

High Energy Astrophysical Phenomena · Physics 2021-02-17 Sean M. Ressler , Eliot Quataert , Christopher J. White , Omer Blaes

We present an analytic, quasi-local model for accretion discs threaded by net, vertical magnetic flux. In a simple slab geometry and ignoring stochastic mean-field dynamo effects, we calculate the large-scale field resulting from the…

High Energy Astrophysical Phenomena · Physics 2024-10-18 Mitchell C. Begelman

We perform two-dimensional, axisymmetric, magnetohydrodynamic simulations of the collapse of a rotating star of 40 Msun and in the light of the collapsar model of gamma-ray burst. Considering two distributions of angular momentum, up to…

We consider dynamo action under the combined influence of turbulence and large-scale shear in sheared jets. Shear can stretch turbulent magnetic field lines in such a way that even turbulent motions showing mirror symmetry become suitable…

Astrophysics · Physics 2009-11-11 V. Urpin

We carried out axisymmetric simulations of disk accretion to a rapidly rotating magnetized star in the "propeller" regime. Simulations show that propellers may be "weak" (with no outflows), and "strong" (with outflows). Investigation of the…

Solar and Stellar Astrophysics · Physics 2009-01-28 M. M. Romanova , R. V. E. Lovelace , G. V. Ustyugova , A. V. Koldoba

We computed the thermal microwave emission from a 3D magnetohydrodynamic (MHD) simulation and compared it with observations of solar jets. The simulation treats the emergence of magnetic flux into the solar atmosphere and its interaction…

Solar and Stellar Astrophysics · Physics 2025-07-23 Costas E. Alissandrakis , Vasilis Archontis , Kostas Moraitis