English
Related papers

Related papers: MRI-driven $\alpha\Omega$ dynamo at high Pm number…

200 papers

Observations of non-thermal emission from several supernova remnants suggest that magnetic fields close to the blastwave are much stronger than would be naively expected from simple shock compression of the field permeating the interstellar…

High Energy Astrophysical Phenomena · Physics 2015-06-05 Luke O'C. Drury , Turlough P. Downes

We present two-dimensional particle-in-cell (PIC) simulations of the fully kinetic collisionless magnetorotational instability (MRI) in weakly magnetized (high $\beta$) pair plasma. The central result of this numerical analysis is the…

High Energy Astrophysical Phenomena · Physics 2018-06-27 Giannandrea Inchingolo , Thomas Grismayer , Nuno F. Loureiro , Ricardo A. Fonseca , Luis O. Silva

Natural dynamos such as planets and stars generate global scale magnetic field despite the inferred presence of small scale turbulence. Such systems are known as large scale dynamos and are typically driven by convection and influenced by…

Fluid Dynamics · Physics 2022-02-24 Ming Yan , Michael A. Calkins

We re-analyze the physical conditions for Magneto-rotational Instability (MRI) within a steady axisymmetric stratified disk of plasma, in order to account for the so-called isorotation theory (the spatial profile of differential angular…

High Energy Astrophysical Phenomena · Physics 2017-04-26 Francesco Cianfrani , Giovanni Montani

Star-forming dwarf galaxies can be seen as the local proxies of the high-redshift building blocks of more massive galaxies according to the current paradigm of the hierarchical galaxy formation. They are low-mass objects, and therefore…

Astrophysics of Galaxies · Physics 2015-06-18 H. Siejkowski , K. Otmianowska-Mazur , M. Soida , D. J. Bomans , M. Hanasz

A new type of instability that is expected to drive magnetohydrodynamic (MHD) turbulence from a purely toroidal magnetic field in an accretion disk is presented. It is already known that in a differentially rotating system, the uniform…

High Energy Astrophysical Phenomena · Physics 2016-05-25 Kota Hirabayashi , Masahiro Hoshino

The saturation level of the magnetorotational instability (MRI) is investigated using three-dimensional MHD simulations. The shearing box approximation is adopted and the vertical component of gravity is ignored, so that the evolution of…

Astrophysics · Physics 2009-11-10 Takayoshi Sano , Shu-ichiro Inutsuka , Neal J. Turner , James M. Stone

We investigate the evolution of hydromagnetic perturbations in a small section of accretion disks. It is known that molecular viscosity is negligible in accretion disks. Hence, it has been argued that a mechanism, known as Magnetorotational…

High Energy Astrophysical Phenomena · Physics 2015-08-12 Sujit Kumar Nath , Banibrata Mukhopadhyay

Accretion disks in which angular momentum transport is dominated by the magnetorotational instability (MRI) can also possess additional, purely hydrodynamic, drivers of turbulence. Even when the hydrodynamic processes, on their own,…

Astrophysics · Physics 2009-11-13 Jared C. Workman , Philip J. Armitage

During stellar evolution, especially in the PMS, stellar structure and rotation evolve significantly causing major changes in the dynamics and global flows of the star. We wish to assess the consequences of these changes on stellar dynamo,…

Solar and Stellar Astrophysics · Physics 2017-09-15 Constance Emeriau-Viard , Allan Sacha Brun

Particle acceleration during the magnetorotational instability (MRI) in a collisionless accretion disk was investigated by using a particle-in-cell (PIC) simulation. We discuss the important role that magnetic reconnection plays not only on…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Masahiro Hoshino

We perform 3D radiation-magnetohydrodynamic simulations of the evolution of the fallback debris after a tidal disruption event. We focus on studying the effects of magnetic fields on the formation and early evolution of the accretion flow.…

High Energy Astrophysical Phenomena · Physics 2025-10-28 Maria Renee Meza , Xiaoshan Huang , Shane W. Davis , Yan-Fei Jiang

We analyze recent high resolution photospheric small-scale dynamo simulations that were computed with the MURaM radiative MHD code. We focus the analysis on newly forming downflow lanes in exploding granules since they show how weakly…

Solar and Stellar Astrophysics · Physics 2018-06-27 Matthias Rempel

Instabilities in relativistic magnetized jets are thought to be deeply connected to their energy dissipation properties and to the consequent acceleration of the non-thermal emitting relativistic particles. Instabilities lead to the…

High Energy Astrophysical Phenomena · Physics 2024-07-23 M. Musso , G. Bodo , G. Mamatsashvili , P. Rossi , A. Mignone

We suggest a new approach that could be used for modeling both the large scale behavior of astrophysical jets and the magnetically dominated explosions in astrophysics. We describe a method for modeling the injection of magnetic fields and…

Astrophysics · Physics 2009-11-11 Hui Li

Using local 3D MHD simulations, we investigate ways in which galactic turbulence associated with the magnetorotational instability (MRI) may influence the formation and properties of GMCs. Our disk models are vertically stratified and…

Astrophysics · Physics 2009-11-10 Woong-Tae Kim , Eve C. Ostriker , James M. Stone

The magnetorotational instability (MRI) is an important process in sufficiently ionized accretion disks, as it can create turbulence that acts as an effective viscosity, mediating angular momentum transport. Due to its local nature, it is…

Earth and Planetary Astrophysics · Physics 2023-09-28 Oliver Zier , Volker Springel

The evolution of large-scale magnetic fields in disk galaxies is investigated numerically. The gasdynamical simulations in a disk perturbed by spiral or bar potential are incorporated into the kinematic calculations of induction equations…

Astrophysics · Physics 2007-05-23 K. Otmianowska-Mazur , M. Chiba

A magnetic disc wind is an important mechanism that may be responsible for driving accretion and structure formation in protoplanetary discs. Recent numerical simulations have shown that these winds can take either the traditional…

Earth and Planetary Astrophysics · Physics 2020-08-19 Philip Kwong Ching Leung , Gordon I. Ogilvie

We use the mean-field dynamo equations to show that an incoherent alpha effect in mirror-symmetric turbulence in a shearing flow can generate a large scale, coherent magnetic field. We illustrate this effect with simulations of a few simple…

Astrophysics · Physics 2015-06-24 Ethan T. Vishniac , Axel Brandenburg