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Related papers: The nonlinear dynamo effect of tearing modes

200 papers

We present results from the first 3D kinetic numerical simulation of magnetorotational turbulence and dynamo, using the local shearing-box model of a collisionless accretion disc. The kinetic magnetorotational instability grows from a…

High Energy Astrophysical Phenomena · Physics 2016-12-07 Matthew W. Kunz , James M. Stone , Eliot Quataert

Boozer addressed the role of magnetic helicity in dynamos [Phys Fluids \textbf{B},(1993)]. He pointed out that the magnetic helicity conservation implies that the dynamo action is more easily attainable if the electric potential varies over…

Plasma Physics · Physics 2009-11-23 Garcia de Andrade

A dynamical approach, rather than the usual statistical approach, is taken to explore the physical mechanisms underlying the nonlinear transfer of energy, the damping of the turbulent fluctuations, and the development of coherent structures…

Solar and Stellar Astrophysics · Physics 2015-08-19 G. G. Howes

Linear gyrokinetic simulations covering the collisional -- collisionless transitional regime of the tearing instability are performed. It is shown that the growth rate scaling with collisionality agrees well with that predicted by a…

Plasma Physics · Physics 2015-05-30 R. Numata , W. Dorland , G. G. Howes , N. F. Loureiro , B. N. Rogers , T. Tatsuno

The topological mapping between a torus of big radius and a sphere is applied to the Riemannian geometry of a stretched and twisted very thick magnetic flux tube, to obtain spherical dynamos solving the magnetohydrodynamics (MHD)…

Astrophysics · Physics 2007-06-20 Garcia de Andrade

We report the results of three-dimensional numerical simulations of convection-driven dynamos in relatively thin rotating spherical shells that show a transition from an strong non-oscillatory dipolar magnetic field to a weaker regularly…

Fluid Dynamics · Physics 2011-02-08 R. D. Simitev , F. H. Busse , A. G. Kosovichev

Plasma turbulence is ubiquitous in space and astrophysical plasmas, playing an important role in plasma energization, but the physical mechanisms leading to dissipation of the turbulent energy remain to be definitively identified. Kinetic…

Solar and Stellar Astrophysics · Physics 2016-12-06 Tak Chu Li , Gregory G. Howes , Kristopher G. Klein , Jason M. TenBarge

This review describes the analytical calculation of lateral pressure profile in lipid membrane with finite curvature. The derivation is based on the previously developed microscopic model of flexible strings [1,2]. According to this theory…

Soft Condensed Matter · Physics 2016-07-08 Anna A. Drozdova

Magnetized turbulence and magnetic reconnection are often invoked to explain the nonthermal emission observed from a wide variety of astrophysical sources. By means of fully-kinetic 2D and 3D PIC simulations, we investigate the interplay…

High Energy Astrophysical Phenomena · Physics 2019-12-04 Luca Comisso , Lorenzo Sironi

We show that the variational energy principle of multi-region relaxed magnetohydrodynamic (MRxMHD) model can be used to predict finite-pressure linear tearing instabilities. In this model, the plasma volume is sliced into sub-volumes…

Plasma Physics · Physics 2023-06-07 A. Kumar , J. Loizu , M. J. Hole , Z. Qu , S. R. Hudson , R. L Dewar

The non-linear interplay between the resistive wall mode (RWM) and the toroidal plasma flow is numerically investigated in a full toroidal geometry, by simultaneously solving the initial value problems for the n=1 RWM and the n=0 toroidal…

Plasma Physics · Physics 2013-05-17 Yueqiang Liu , Youwen Sun

On the basis of three-dimensional nonlinear magnetohydrodynamic simulations, we propose a new dynamical process leading to the stochastization of magnetic fields during an edge pedestal collapse. Primary tearing modes are shown to grow by…

Plasma Physics · Physics 2015-06-23 Tongnyeol Rhee , Sung Sik Kim , Hogun Jhang , Gun Young Park , Raghvendra Singh

Recent analytical works on strong magnetized plasma turbulence have hypothesized the existence of a range of scales where the tearing instability may govern the energy cascade. In this paper, we estimate the conditions under which such…

Plasma Physics · Physics 2020-02-19 Nuno F. Loureiro , Stanislav Boldyrev

The magnetohydrodynamic dynamo equation is derived within general relativity, using the covariant 1+3 approach, for a plasma with finite electric conductivity. This formalism allows for a clear division and interpretation of plasma and…

Astrophysics · Physics 2009-11-10 Mattias Marklund , Chris Clarkson

The properties of current sheets forming in a ion-kinetically turbulent collisionless plasma are investigated by utilizing the results of two-dimensional hybrid-kinetic numerical simulations. For this sake the algorithm proposed by Zhdankin…

Plasma Physics · Physics 2024-06-19 Amirhassan Chatraee Azizabadi , Neeraj Jain , Jörg Büchner

The weak collisionality typical of turbulence in many diffuse astrophysical plasmas invalidates an MHD description of the turbulent dynamics, motivating the development of a more comprehensive theory of kinetic turbulence. In particular, a…

Solar and Stellar Astrophysics · Physics 2015-02-17 Gregory G. Howes

This study delves into Microtearing Modes (MTMs) in tokamak plasmas, employing advanced simulations within the BOUT++ framework. The research, centering on collisional MTMs influenced by the time-dependent thermal force, enhances our…

Plasma Physics · Physics 2024-04-15 Kaixuan Fan , Xue-Qiao Xu , Ben Zhu , Chao Dong , Tianyang Xia , Zeyu Li

We study a new type of large-scale instability, which arises in obliquely rotating stratified electroconductive fluid with an external uniform magnetic field and a small-scale external force having zero helicity. This force gives rise to…

Fluid Dynamics · Physics 2018-07-06 M. I. Kopp , K. N. Kulik , A. V. Tur , V. V. Yanovsky

We extend the standard two-scale theory of the turbulent dynamo coefficient $\alpha$ to include the nonlinear back reaction of the mean field $\bar B$ on the turbulence. We calculate the turbulent emf as a power series in $\bar B$, assuming…

Astrophysics · Physics 2009-10-31 George B. Field , Eric G. Blackman , Hongsong Chou

We calculate the stability of a multiple relaxation region MHD (MRXMHD) plasma, or stepped-Beltrami plasma, using both variational and tearing mode treatments. The configuration studied is a periodic cylinder. In the variational treatment,…

Plasma Physics · Physics 2015-05-13 M. J. Hole , R. Mills , S. R. Hudson , R. L. Dewar