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Related papers: The nonlinear dynamo effect of tearing modes

200 papers

A three-dimensional numerical computation of magnetohydrodynamic dynamo behavior is described. The dynamo is mechanically forced with a driving term of the Taylor-Green type. The magnetic field development is followed from negligibly small…

Astrophysics · Physics 2007-05-23 P. D. Mininni , Y. Ponty , D. C. Montgomery , J. -F. Pinton , H. Politano , A. Pouquet

A general nonlinear dispersion relation is derived in a nondifferential form for an adiabatic sinusoidal Langmuir wave in collisionless plasma, allowing for an arbitrary distribution of trapped electrons. The linear dielectric function is…

Plasma Physics · Physics 2015-05-28 I. Y. Dodin , N. J. Fisch

We present results of 2D and 3D PIC simulations of magnetic turbulence production by isotropic cosmic-ray ions drifting upstream of SNR shocks. The studies aim at testing recent predictions of a strong amplification of short wavelength…

Astrophysics · Physics 2009-11-13 Jacek Niemiec , Martin Pohl , Thomas Stroman , and Ken-Ichi Nishikawa

The adiabatic limit of a recently proposed dynamical extension of Taylor relaxation, \emph{multi-region relaxed magnetohydrodynamics} (MRxMHD) is summarized, with special attention to the appropriate definition of relative magnetic…

Plasma Physics · Physics 2017-04-05 Robert L. Dewar , Stuart R. Hudson , Amitava Bhattacharjee , Zensho Yoshida

We consider the problem of incompressible, forced, nonhelical, homogeneous and isotropic MHD turbulence with no mean magnetic field and large magnetic Prandtl number. This type of MHD turbulence is the end state of the turbulent dynamo,…

We investigate a role of the Hall-effect in the current sheet evolution and onset of the secondary tearing (plasmoid) instability in the framework of the incompressible resistive Hall-magnetohydrodynamics (MHD). The model under…

Plasma Physics · Physics 2017-04-24 G. Vekstein , K. Kusano

Within the traditional frame of reduced MHD, a new rigorous perturbation expansion provides the equation ruling the nonlinear growth and saturation of the tearing mode for any current gradient. The small parameter is the magnetic island…

Plasma Physics · Physics 2007-05-23 N. Arcis , D. F. Escande , M. Ottaviani

A rigorous theory for the generation of a large-scale magnetic field by random non-helically forced motions of a conducting fluid combined with a linear shear is presented in the analytically tractable limit of low Rm and weak shear. The…

Astrophysics · Physics 2011-12-15 T. Heinemann , J. C. McWilliams , A. A. Schekochihin

To understand the basic mechanism of the formation of magnetic flux concentrations, we determine by direct numerical simulations the turbulence contributions to the mean magnetic pressure in a strongly stratified isothermal layer with large…

Solar and Stellar Astrophysics · Physics 2015-03-17 Axel Brandenburg , Koen Kemel , Nathan Kleeorin , Igor Rogachevskii

We propose that pressure anisotropy causes weakly collisional turbulent plasmas to self-organize so as to resist changes in magnetic-field strength. We term this effect "magneto-immutability" by analogy with incompressibility (resistance to…

High Energy Astrophysical Phenomena · Physics 2019-02-27 Jonathan Squire , Alexander A. Schekochihin , Eliot Quataert , Matthew W. Kunz

We investigate numerically magnetic field generation by thermal convection with square periodicity cells in a rotating horizontal layer of electrically-conducting fluid with stress-free electrically perfectly conducting boundaries for…

Chaotic Dynamics · Physics 2010-04-12 V. Zheligovsky

A new kind of dynamo utilizing flowing laboratory plasmas has been identified. Conversion of plasma kinetic energy to magnetic energy is verified numerically by kinematic dynamo simulations for magnetic Reynolds numbers above 210. As…

Astrophysics · Physics 2009-11-07 Zhehui Wang , Vladimir I. Pariev , Cris W. Barnes , Daniel C. Barnes

Several recent advances in turbulent dynamo theory are reviewed. High resolution simulations of small-scale and large-scale dynamo action in periodic domains are compared with each other and contrasted with similar results at low magnetic…

Solar and Stellar Astrophysics · Physics 2012-07-10 Axel Brandenburg , Dmitry Sokoloff , Kandaswamy Subramanian

For short wavelengths, it is well known that the linearized Wigner-Moyal equation predicts wave damping due to wave-particle interaction, where the resonant velocity shifted from the phase velocity by a velocity $v_q = \hbar k/2m$. Here…

Plasma Physics · Physics 2017-11-15 Gert Brodin , Robin Ekman , Jens Zamanian

It has recently been demonstrated experimentally that a turbulent plasma created by the collision of two inhomogeneous, asymmetric, weakly magnetised laser-produced plasma jets can generate strong stochastic magnetic fields via the…

The linear threshold condition of the mirror mode including weak drift and finite Larmor radius effects is analysed and shown that it can be given to arbitrary precision in closed analytical form. Combined with observations of mirror modes…

Space Physics · Physics 2009-03-14 R. A. Treumann , O. D. Constantinescu

We study the long term evolution of magnetic fields generated by a collisionless relativistic $e^+e^-$ shock which is initially unmagnetized. Our 2D particle-in-cell numerical simulations show that downstream of such a Weibel-mediated…

Astrophysics · Physics 2009-11-13 P. Chang , A. Spitkovsky , J. Arons

The effects of negative triangularity (NT) on boundary plasma turbulence in double-null (DN) configurations are investigated using global, nonlinear, three-dimensional, flux-driven two-fluid simulations. NT plasmas exhibit suppressed…

Plasma Physics · Physics 2024-12-31 Kyungtak Lim , Paolo Ricci , Leonard Lebrun

Shocks waves are a ubiquitous feature of many astrophysical plasma systems, and an important process for energy dissipation and transfer. The physics of these shock waves are frequently treated/modeled as a collisional, fluid MHD…

Plasma Physics · Physics 2021-11-17 Colby C. Haggerty , Antoine Bret , Damiano Caprioli

In the presence of a strong uniform magnetic field, we study the influence of space noncommutativity on the electromagnetic waves propagating through a quasi-static homogeneous plasma. In this treatment, we have adopted a physical model…

High Energy Physics - Theory · Physics 2008-11-26 S. Bourouaine , A. Benslama