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The asymptotic structure of outflows from rotating magnetized objects confined by a uniform external pressure is calculated. The flow is assumed to be perfect MHD, polytropic, axisymmetric and stationary. The well known associated first…

Astrophysics · Physics 2007-05-23 Thibaut Lery , J. Heyvaerts , S. Appl , C. A. Norman

We investigate the build-up of the galactic dynamo and subsequently the origin of a magnetic driven outflow. We use a setup of an isolated disc galaxy with a realistic circum-galactic medium (CGM). We find good agreement of the galactic…

Astrophysics of Galaxies · Physics 2020-04-01 Ulrich P. Steinwandel , Klaus Dolag , Harald Lesch , Benjamin P. Moster , Andreas Burkert , Almudena Prieto

A new type of wind - a conical wind - has been discovered in axisymmetric magnetohydrodynamic simulations of the disk-magnetosphere interaction in cases where the magnetic field of the star is bunched into an X-type configuration. Such a…

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

We present the effects of ordered large scale magnetic field on the structure of supercritical accretion flow in the presence of outflow. In the cylindrical coordinates ($r, \varphi,z$), We write the 1.5 dimensional, the steady state…

High Energy Astrophysical Phenomena · Physics 2017-06-21 Maryam Ghasemnezhad , Shahram Abbassi

We numerically investigate the dynamics of a 2D non-magnetised protoplanetary disc surrounded by an inflow coming from an external envelope. We find that the accretion shock between the disc and the inflow is unstable, leading to the…

Solar and Stellar Astrophysics · Physics 2015-10-14 Geoffroy Lesur , Patrick Hennebelle , Sébastien Fromang

The elements of the cold magnetic driven flows behave like beads on the magnetic field line. The inclination of the field lines at the surface of the disc plays a crucial role on the nature of the magnetically driven outflow. For the…

High Energy Astrophysical Phenomena · Physics 2015-05-18 Xinwu Cao

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

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

This paper explores the effects of large-scale magnetic fields in hot accretion flows for asymmetric configurations with respect to the equatorial plane. The solutions that we have found show that the large-scale asymmetric magnetic field…

High Energy Astrophysical Phenomena · Physics 2017-07-26 Maryam Samadi , Shahram Abbassi , Richard Lovelace

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

We consider the effect of vertical outflows on the mean-field dynamo in a thin disk. These outflows could be due to winds or magnetic buoyancy. We analyse both two-dimensional finite-difference numerical solutions of the axisymmetric dynamo…

Astrophysics · Physics 2009-10-31 A. Bardou , B. v. Rekowski , W. Dobler , A. Brandenburg , A. Shukurov

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

We carried out global three-dimensional magneto-hydrodynamic simulations of dynamo activities in galactic gaseous disks without assuming equatorial symmetry. Numerical results indicate the growth of azimuthal magnetic fields non-symmetric…

Astrophysics of Galaxies · Physics 2015-06-12 Mami Machida , Kenji E. Nakamura , Takahiro Kudoh , Takuya Akahori , Sofue Yoshiaki , Ryoji Matsumoto

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 report the results of a magneto-hydrodynamic (MHD) simulation of a convective dynamo in a model solar convective envelope driven by the solar radiative diffusive heat flux. The convective dynamo produces a large-scale mean magnetic field…

Solar and Stellar Astrophysics · Physics 2014-06-18 Yuhong Fan , Fang Fang

Galactic outflows, driven by active galactic nuclei (AGN), play a crucial role in galaxy formation and in the self-regulated growth of supermassive black holes (BHs). AGN feedback couples to and affects gas, rather than stars, and in many,…

Astrophysics of Galaxies · Physics 2018-04-10 Tilman Hartwig , Marta Volonteri , Gohar Dashyan

We show that a large-scale, weak magnetic field threading a turbulent accretion disk tends to be advected inward, contrary to previous suggestions that it will be stopped by outward diffusion. The efficient inward transport is a consequence…

Astrophysics · Physics 2009-11-13 David M. Rothstein , Richard V. E. Lovelace

It is shown that a dynamo can operate in an Active Galactic Nuclei accretion disk due to the Keplerian shear and due to the helical motions of expanding and twisting plumes of plasma heated by many star passages through the disk. Each plume…

Astrophysics · Physics 2009-01-19 Vladimir I. Pariev , Stirling A. Colgate , John M. Finn

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

We study mass accretion and ejection in the vicinity of massive star forming cores using high-resolution (5 au) 3D AMR numerical simulations. We investigate the mechanisms at the origin of outflows and characterise the properties of the…

Solar and Stellar Astrophysics · Physics 2022-02-02 Benoît Commerçon , Matthias González , Raphaël Mignon-Risse , Patrick Hennebelle , Neil Vaytet