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Related papers: Protostellar jets and magnetic diffusion

200 papers

We present the results of 2.5-dimensional resistive magnetohydrodynamic (MHD) simulations of the magnetic interaction between a weakly magnetized neutron star and its accretion disk. General relativistic effects are simulated by using the…

Astrophysics · Physics 2009-11-10 Yoshiaki Kato , Mitsuru Hayashi , Ryoji Matsumoto

We use axisymmetric magnetohydrodynamic (MHD) simulations to investigate the launching and collimation of jets emerging from the disk-magnetosphere boundary of accreting magnetized stars. Our analysis shows that the matter flows into the…

Solar and Stellar Astrophysics · Physics 2012-01-25 Patrick S Lii , Marina M. Romanova , Richard V. Lovelace

We have carried out and analyzed a set of axisymmetric MHD simulations of the evolution of a turbulent/diffusive accretion disc around an initially unmagnetized star. The disc is initially threaded by a weak magnetic field where the…

High Energy Astrophysical Phenomena · Physics 2015-06-12 S. Dyda , R. V. E. Lovelace , G. V. Ustyugova , P. S. Lii , M. M. Romanova , A. V. Koldoba

The interaction between a protostellar magnetosphere and a surrounding dynamo-active accretion disc is investigated using an axisymmetric mean-field model. In all models investigated, the dynamo-generated magnetic field in the disc arranges…

Astrophysics · Physics 2009-11-10 Brigitta von Rekowski , Axel Brandenburg

Stellar magnetosphere and accretion disk interact, and a result should be outflow launched from the innermost vicinity of a protostellar object. We simulated physical conditions in this region by resistive MHD simulations. Outflows…

Solar and Stellar Astrophysics · Physics 2009-08-19 Miljenko Cemeljic , Hsien Shang , Tzu-Yang Chiang

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

Starting from a prestellar core with a size of $1.2\times10^4$ AU, we calculate the evolution of a gravitationally collapsing core until $\sim2000$ yr after protostar formation using a three-dimensional resistive magnetohydrodynamic…

Solar and Stellar Astrophysics · Physics 2019-05-29 Masahiro N. Machida , Shantanu Basu

We present multi-dimensional simulations of magnetized radiative jets appropriate to Young Stellar Objects. Magnetized jets subject to collisionally excited radiative losses have not, as yet, received extensive scrutiny. The purpose of this…

Astrophysics · Physics 2009-10-30 A. Frank , D. Ryu , T. W. Jones , A. Noriega-Crespo

We present the results of a global, three-dimensional magnetohydrodynamics simulation of an accretion disk with a rotating, weakly magnetized central star. The disk is threaded by a weak, large-scale poloidal magnetic field, and the central…

Solar and Stellar Astrophysics · Physics 2019-02-07 Shinsuke Takasao , Kengo Tomida , Kazunari Iwasaki , Takeru K. Suzuki

We investigate the launching of jets and outflows from magnetically diffusive accretion disks. Using the PLUTO code we solve the time-dependent resistive MHD equations taking into account the disk and jet evolution simultaneously. The main…

High Energy Astrophysical Phenomena · Physics 2015-06-05 Somayeh Sheikhnezami , Christian Fendt , Oliver Porth , Bhargav Vaidya , Jamshid Ghanbari

This is a doctorate level lecture on the physics of accretion discs driving magnetically self-confined jets, usually referred to in the literature as disc winds. I will first review the governing magnetohydrodynamic equations and then…

Astrophysics · Physics 2008-11-26 Jonathan Ferreira

We present results of axisymmetic magnetohydrodynamic simulations of the interaction of a rapidly-rotating, magnetized star with an accretion disk. The disk is considered to have a finite viscosity and magnetic diffusivity. The main…

Astrophysics · Physics 2009-11-11 G. V. Ustyugova , A. V. Koldoba , M. M. Romanova , R. V. E. Lovelace

We investigate the dissipation of magnetic flux in primordial star-forming clouds throughout their collapse including the run-away collapse phase as well as the accretion phase. We solve the energy equation and the non-equilibrium chemical…

Astrophysics · Physics 2019-08-19 Hideki Maki , Hajime Susa

We study the evolution of the protoplanetary discs (PPDs) in the presence of magnetically driven winds with the stress relations motivated by the non-ideal MHD disc simulations. Contribution of the magnetic winds in the angular momentum…

Astrophysics of Galaxies · Physics 2019-07-31 Mohsen Shadmehri , Sayyedeh Masoumeh Ghoreyshi

The formation of astrophysical objects of different nature and size, from black holes to gaseous giant planets, involves a disk-jet system, where the disk drives the mass accretion onto a central compact object and the jet is a fast…

Solar and Stellar Astrophysics · Physics 2022-09-02 Luca Moscadelli , Alberto Sanna , Henrik Beuther , André Oliva , Rolf Kuiper

In this paper we present steady-state RMHD simulations that include a mass-load term to study the process of jet deceleration. The mass-load mimics the injection of a proton-electron plasma from stellar winds within the host galaxy into…

High Energy Astrophysical Phenomena · Physics 2020-10-28 Andreu Anglés-Castillo , Manel Perucho , José María Martí , Robert A. Laing

An analytic model is developed for the erosion of protoplanetary gas discs by high velocity magnetized stellar winds. The winds are centrifugally driven from the surface of rapidly rotating, strongly magnetized young stars. The presence of…

Solar and Stellar Astrophysics · Physics 2015-06-19 Neesha R. Schnepf , Richard V. E. Lovelace , Marina Romanova , Vladimir Airapetian

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

Recent observations uncover various phenomena around the protostar such as misalignment between the outflow and magnetic field, precession of the jet, and time variability of the ejected clumps, whose origins are under debate. We perform a…

Solar and Stellar Astrophysics · Physics 2019-03-20 Shingo Hirano , Masahiro N. Machida

We present a 3-D ideal MHD simulation of magnetospheric accretion onto a non-rotating star. The accretion process unfolds with intricate 3-D structures driven by various mechanisms. First, the disc develops filaments at the magnetospheric…

Solar and Stellar Astrophysics · Physics 2023-12-18 Zhaohuan Zhu , James M. Stone , Nuria Calvet