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Related papers: Protostellar jets and magnetic diffusion

200 papers

A review is made of recent magnetohydrodynamic (MHD) theory and simulations of origin of jets from accretion disks. Many compact astrophysical objects emit powerful, highly-collimated, oppositely directed jets. Included are the extra…

Astrophysics · Physics 2007-05-23 R. V. E. Lovelace , G. V. Ustyugova , A. V. Koldoba

We use one-dimensional two-zone time-dependent accretion disk models to study the long-term evolution of protostellar disks subject to mass addition from the collapse of a rotating cloud core. Our model consists of a constant surface…

Solar and Stellar Astrophysics · Physics 2015-05-18 Zhaohuan Zhu , Lee Hartmann , Charles Gammie

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…

The theory of jet emitting disks (JEDs) provides a mathematical framework for a self-consistent treatment of steady-state accretion and ejection. A large-scale vertical magnetic field threads the accretion disk where magnetic turbulence…

High Energy Astrophysical Phenomena · Physics 2024-12-11 N. Zimniak , J. Ferreira , J. Jacquemin-Ide

We investigate the formation of an ideal magnetized jet that originates from a disk acting as a boundary by conducting axisymmetric MHD simulations. Our simulations demonstrate that the magnetized jet is consistently launched and reaches a…

High Energy Astrophysical Phenomena · Physics 2024-03-06 Somayeh Sheikhnezami , Mostafa Sepahvand

Recent surveys show that protoplanetary disks have lower levels of turbulence than expected based on their observed accretion rates. A viable solution to this is that magnetized disk winds dominate angular momentum transport. This has…

Earth and Planetary Astrophysics · Physics 2022-08-17 Matthew Alessi , Ralph E. Pudritz

Aims: We investigate the evolution of protoplanetary discs (PPDs hereafter) with magnetically driven disc winds and viscous heating. Methods: We consider an initially massive disc with ~0.1 Msun to track the evolution from the early stage…

Earth and Planetary Astrophysics · Physics 2016-12-07 Takeru K. Suzuki , Masahiro Ogihara , Alessandro Morbidelli , Aurélien Crida , Tristan Guillot

We study the launching of magnetized jets from a resistive circumstellar disk within a binary system, employing a unique combination of 3D MHD jet launching simulations (PLUTO code) and post-processed 3D radiative transfer modeling…

High Energy Astrophysical Phenomena · Physics 2025-04-16 Somayeh Sheikhnezami , Christian Fendt , Sareh Ataiee

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

Interstellar magnetic fields influence all stages of the process of star formation, from the collapse of molecular cloud cores to the formation of protostellar jets. This requires us to have a full understanding of the physical properties…

Astrophysics · Physics 2009-11-13 Cecilia Pinto , Daniele Galli , Francesca Bacciotti

The magneto-centrifugal model for jet formation is studied by time-dependent simulations reaching steady state in a cold gas with negligible fluid pressure, in an axisymmetric geometry, using a modification of the Zeus3D code adapted to…

Astrophysics · Physics 2009-10-31 R. Krasnopolsky , Z. -Y. Li , R. D. Blandford

Star formation is usually accompanied by outflow phenomena. There is strong evidence that these outflows and jets are launched from the protostellar disk by magneto-rotational processes. Here, we report on our three dimensional, adaptive…

Astrophysics · Physics 2009-11-13 Robi Banerjee , Ralph E. Pudritz

Torque fluctuations due to magnetorotational turbulence in proto-planetary disks may greatly influence the migration patterns and survival probabilities of nascent planets. Provided that the turbulence is a stationary stochastic process…

Astrophysics · Physics 2008-11-26 Eric T. Johnson , Jeremy Goodman , Kristen Menou

Using resistive magnetohydrodynamics simulations, the propagation of protostellar jets, the formation of circumstellar discs and the configuration of magnetic fields are investigated from the prestellar cloud phase until $\sim$500 yr after…

Solar and Stellar Astrophysics · Physics 2020-01-08 Masahiro N. Machida , Shingo Hirano , Hideyuki Kitta

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 present the first-ever simulations of non-ideal magnetohydrodynamical (MHD) stellar magnetospheric winds coupled with disc-driven jets where the resistive and viscous accretion disc is self-consistently described. These innovative MHD…

Astrophysics · Physics 2011-02-19 Z. Meliani , F. Casse , C. Sauty

Large scale magnetic field threading an accretion disk is a key ingredient in the jet formation model. The most attractive scenario for the origin of such a large scale field is the advection of the field by the gas in the accretion disk…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Xinwu Cao , H. C. Spruit

We present the results of a series of axisymmetric time-dependent magnetohydrodynamic (MHD) simulations of the propagation of cooling, overdense jets, motivated by the properties of outflows associated with young stellar objects. A variety…

Astrophysics · Physics 2009-10-31 James M. Stone , Philip E. Hardee

We perform state-of-the-art, 3D, time-dependent simulations of magnetized disk winds, carried out to simulation scales of 60 Astronomical Units, in order to confront optical HST observations of protostellar jets. We ``observe'' the optical…

Solar and Stellar Astrophysics · Physics 2015-05-19 Jan Staff , Brian Niebergal , Rachid Ouyed , Ralph Pudritz , Kai Cai

The transport of angular momentum is capital during the formation of low-mass stars; too little removal and rotation ensures stellar densities are never reached, too much and the absence of rotation means no protoplanetary disks can form.…

Solar and Stellar Astrophysics · Physics 2018-07-04 Neil Vaytet , Benoît Commerçon , Jacques Masson , Matthias González , Gilles Chabrier
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