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Related papers: On fan-shaped cold MHD winds from Keplerian accret…

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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

In this lecture I review the theory of magnetized accretion discs driving jets, with a focus on Young Stellar Objects (YSOs). I first introduce observational and theoretical arguments in favor of the ``disc wind'' paradigm. There, accretion…

Astrophysics · Physics 2007-05-23 Jonathan Ferreira

Many astrophysical sources, e.g., cataclysmic variables, X-ray binaries, active galactic nuclei, exhibit a wind outflow, when they reveal a multicolor blackbody spectrum, hence harboring a geometrically thin Keplerian accretion disk. Unlike…

High Energy Astrophysical Phenomena · Physics 2021-06-14 Nagendra Kumar , Banibrata Mukhopadhyay

Numerical simulations of outflows formed during the collapse of 100 M_sun cloud cores are presented. We derive a generalised criterion from MHD wind theory to analyse the launching mechanism of these outflows. The criterion is successfully…

Solar and Stellar Astrophysics · Physics 2015-05-30 D. Seifried , R. E. Pudritz , R. Banerjee , D. Duffin , R. S. Klessen

We explore the pulsationally driven orbital mass ejection mechanism for Be star disc formation using isothermal, 3D magnetohydrodynamic (MHD) and hydrodynamic simulations. Non-radial pulsations are added to a star rotating at 95\% of…

Solar and Stellar Astrophysics · Physics 2021-11-09 Sean M. Ressler

Context. Current research has established magnetised disc winds as a promising way of driving accretion in protoplanetary discs. Aims. We investigate the evolution of large protoplanetary disc populations under the influence of magnetically…

Earth and Planetary Astrophysics · Physics 2023-06-21 Jesse Weder , Christoph Mordasini , Alexandre Emsenhuber

The conventional accretion disk lore is that magnetized turbulence is the principal angular momentum transport process that drives accretion. However, when dynamically important large-scale magnetic fields thread an accretion disk, they can…

High Energy Astrophysical Phenomena · Physics 2024-04-24 Vikram Manikantan , Nicholas Kaaz , Jonatan Jacquemin-Ide , Gibwa Musoke , Koushik Chatterjee , Matthew Liska , Alexander Tchekhovskoy

The evolution of protoplanetary discs and the related process of planet formation is regulated by angular momentum transport and mass-loss processes. Over the past decade, the paradigm of viscosity has been challenged and MHD disc winds…

Solar and Stellar Astrophysics · Physics 2021-12-08 Benoît Tabone , Giovanni P. Rosotti , Alexander J. Cridland , Philip J. Armitage , Giuseppe Lodato

We investigate the launching of outflows from the disk-magnetosphere boundary of slowly and rapidly rotating magnetized stars using axisymmetric and exploratory 3D magnetohydrodynamic (MHD) simulations. We find long-lasting outflows in both…

Solar and Stellar Astrophysics · Physics 2015-05-13 M. M. Romanova , G. V. Ustyugova , A. V. Koldoba , R. V. E. Lovelace

We present MHD simulations exploring the launching, acceleration and collimation of jets and disk winds. The evolution of the disk structure is consistently taken into account. Extending our earlier studies, we now consider the…

High Energy Astrophysical Phenomena · Physics 2015-06-23 Deniss Stepanovs , Christian Fendt , Somayeh Sheikhnezami

The recent advent of spatially resolved mm- and cm-wavelength polarimetry in protostellar accretion discs could help clarify the role of magnetic fields in the angular momentum transport in these systems. The best case to date is that of…

Solar and Stellar Astrophysics · Physics 2016-09-07 Titos Matsakos , Petros Tzeferacos , Arieh Königl

We present self-similar models of resistive viscous Keplerian disks driving non-relativistic magnetohydrodynamics (MHD) jets becoming super fast-magnetosonic. We show that in order to obtain such solutions, the thermal pressure must be a…

Astrophysics · Physics 2009-11-10 Jonathan Ferreira , Fabien Casse

We review recent observational and theoretical results on the relationship between circumstellar accretion disks and jets in young stellar objects. We then present a theoretical framework that interprets jets as accretion-powered,…

Astrophysics · Physics 2007-05-23 Arieh Konigl , Ralph E. Pudritz

A large body of theoretical and computational work shows that jets - modelled as magnetized disk winds - exert an external torque on their underlying disks that can efficiently remove angular momentum and act as major drivers of disk…

Astrophysics · Physics 2009-11-11 Ralph E. Pudritz , Robi Banerjee

The presence of an imposed external magnetic field may drastically influence the structure of thin accretion discs. The magnetic field energy is here assumed to be in balance with the thermal energy of the accretion flow. The vertical…

Astrophysics · Physics 2007-05-23 G. Rudiger , D. A. Shalybkov

We analyzed the results of non-linear resistive magnetohydrodynamical (MHD) simulations of jet formation to study the acceleration mechanism of axisymmetric, resistive MHD jets. The initial state is a constant angular momentum, polytropic…

Astrophysics · Physics 2009-11-10 T. Kuwabara , K. Shibata , T. Kudoh , R. Matsumoto

We study a model of weakly ionized, protostellar accretion discs that are threaded by a large-scale, ordered magnetic field and power a centrifugally driven wind. We consider the limiting case where the wind is the main repository of the…

Solar and Stellar Astrophysics · Physics 2015-05-14 A. Königl , R. Salmeron , M. Wardle

We present steady-state solutions for a one-dimensional, magnetically-driven accretion disk wind model based on magnetohydrodynamic equations. We assume a geometrically thin, gas-pressure-dominated accretion disk, incorporating both…

High Energy Astrophysical Phenomena · Physics 2025-01-23 Mageshwaran Tamilan , Kimitake Hayasaki , Takeru K. Suzuki

Observations of jets from young stellar objects reveal the asymmetric outflows from some sources. A large set of $2.5$D MHD simulations has been carried out for axisymmetric viscous/diffusive disc accretion to rotating magnetized stars for…

High Energy Astrophysical Phenomena · Physics 2015-06-23 Sergei Dyda , Richard V. E. Lovelace , Galina V. Ustyugova , Patrick S. Lii , Marina M. Romanova , Alexander V. Koldoba

Strong evidence is emerging that winds can be driven from the central regions of accretion disks in both active galactic nuclei (AGN) and Galactic black hole binaries (GBHBs). Direct evidence for highly-ionized, Compton-thin inner-disk…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Christopher S. Reynolds