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Related papers: Magnetic dynamo action in helical turbulence

200 papers

We explain the (non)helical dynamo process using a field-structure model based on magnetic induction equation in an intuitive way. We show how nonhelical kinetic energy converts into magnetic energy and cascades toward smaller eddies in a…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-27 Kiwan Park

Several lines of evidence suggest that protogalactic and galactic environments manage to grow magnetic field very rapidly. This makes the theoretical problem of achieving rapid growth of magnetic fields in such environments difficult.…

Astrophysics · Physics 2009-11-10 D. S. Balsara , J. S. Kim , M. M. Mac Low , G. Mathews

We study the Lagrangian mechanism of the fluctuation dynamo at zero Prandtl number and infinite magnetic Reynolds number, in the Kazantsev-Kraichnan model of white-noise advection. With a rough velocity field corresponding to a turbulent…

Plasma Physics · Physics 2011-03-07 Gregory L. Eyink

We have studied the large scale dynamo process forced with helical magnetic energy. The magnetically driven dynamo is not so well studied as kinetically forced dynamo. It has been thought to represent the amplification of magnetic field in…

Plasma Physics · Physics 2021-09-21 Kiwan Park , Myung-Ki Cheoun

We argue that the recently reported Kolmogorov-like magnetic turbulence spectrum in the cool core of the Hydra A galaxy cluster can be understood by kinetic energy injection by active galaxies that drives a turbulent non-helical magnetic…

Astrophysics · Physics 2009-11-11 T. A. Ensslin , C. Vogt

Spectral transfer processes in magnetohydrodynamic (MHD) turbulence are investigated analytically by decomposition of the velocity and magnetic fields in Fourier space into helical modes. Steady solutions of the dynamical system which…

Fluid Dynamics · Physics 2016-02-18 Moritz F. Linkmann , Arjun Berera , Mairi E. McKay , Julia Jäger

By performing a global magnetohydrodynamical (MHD) simulation for the Milky Way with an axisymmetric gravitational potential, we propose that spatially dependent amplification of magnetic fields possibly explains the observed noncircular…

Astrophysics of Galaxies · Physics 2017-02-22 Takeru K. Suzuki , Yasuo Fukui , Kazufumi Torii , Mami Machida , Ryoji Matsumoto , Kensuke Kakiuchi

Using a rotating flat layer heated from below as an example, we consider effects which lead to stabilizing an exponentially growing magnetic field in magnetostrophic convection in transition from the kinematic dynamo to the full non-linear…

Fluid Dynamics · Physics 2015-05-18 P. Hejda , M. Reshetnyak

Renormalized viscosity, renormalized resistivity, and various energy fluxes are calculated for helical magnetohydrodynamics using perturbative field theory. The calculation is to first-order in perturbation. Kinetic and magnetic helicities…

Chaotic Dynamics · Physics 2008-11-26 Mahendra K. Verma

This paper concerns kinematic helical dynamos in a spherical fluid body surrounded by an insulator. In particular, we examine their behaviour in the regime of large magnetic Reynolds number $\Rm$, for which dynamo action is usually…

Earth and Planetary Astrophysics · Physics 2015-05-19 Henrik Latter , David Ivers

Nonresonant current instability was identified by Bell (2004) as an important mechanism for magnetic field amplification in supernova remnants. In this paper we focus on studying the nonlinear stage of this instability using the…

Astrophysics of Galaxies · Physics 2014-06-06 Andrey Beresnyak , Hui Li

Based on the new findings on the turbulent dynamo in \citet{XL16}, we examine the magnetic field amplification in the context of supernova remnants. Due to the strong ion-neutral collisional damping in the weakly-ionized interstellar…

High Energy Astrophysical Phenomena · Physics 2017-12-13 Siyao Xu , Alex Lazarian

Analytical solution of ${\alpha}$-dynamo equation representing strongly torsioned helical dynamo is obtained in the thin twisted Riemannian flux tubes approximation. The $\alpha$ factor possesses a fundamental contribution from torsion…

Astrophysics · Physics 2007-12-27 Garcia de Andrade

Helical magnetic background fields with adjustable pitch angle are imposed on a conducting fluid in a differentially rotating cylindrical container. The small-scale kinetic and current helicities are calculated for various field geometries,…

Solar and Stellar Astrophysics · Physics 2015-05-20 M. Gellert , G. Ruediger , R. Hollerbach

We consider a neutral holographic plasma with dynamical electromagnetic interactions in a finite external magnetic field. The Coulomb interactions are introduced via mixed boundary conditions for the Maxwell gauge field. The collective…

High Energy Physics - Theory · Physics 2021-06-07 Matteo Baggioli , Ulf Gran , Marcus Tornsö

An extended, spinless Falicov-Kimball model in the presence of perpendicular magnetic field is investigated employing Hartree-Fock self-consistent mean-field theory in two dimensions. In the presence of an orbital field the…

Strongly Correlated Electrons · Physics 2017-03-08 S. Pradhan , A. Taraphder

Using the magnetohydrodynamic (MHD) description, we develop a nonlinear dynamo model that couples the evolution of the large scale magnetic field with turbulent dynamics of the plasma at small scale by electromotive force (e.m.f.) in the…

Earth and Planetary Astrophysics · Physics 2011-09-29 Giuseppina Nigro , Pierlugi Veltri

We carried out a parameter study of interacting disk galaxies with impact parameters ranging from central collisions to weakly interacting scenarios. The orientations of the disks were also varied. In particular, we investigated how…

Astrophysics of Galaxies · Physics 2024-09-18 Simon Selg , Wolfram Schmidt

Models of large scale (magnetohydrodynamic) dynamos (LSD) which couple large scale field growth to total magnetic helicity evolution best predict the saturation of LSDs seen in simulations. For the simplest so called "{\alpha}2" LSDs in…

Plasma Physics · Physics 2015-06-03 Kiwan Park , E. G. Blackman

The evolution of the magnetic helicity tensor for a nonzero mean magnetic field and for large magnetic Reynolds numbers in an anisotropic turbulence is studied. It is shown that the isotropic and anisotropic parts of the magnetic helicity…

Astrophysics · Physics 2008-11-26 N. Kleeorin , I. Rogachevskii