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Related papers: Study on the large scale dynamo transition

200 papers

Weakly-collisional plasmas, such as the solar wind or the intra-cluster medium (ICM) of galaxy clusters, evolve in the presence of dynamically strong magnetic fields. The turbulent dynamo can amplify magnetic fields to such levels by…

Astrophysics of Galaxies · Physics 2025-02-11 Radhika Achikanath Chirakkara , Christoph Federrath , Amit Seta

Using a closure model for the evolution of magnetic correlations, we uncover an interesting plausible saturated state of the small-scale fluctuation dynamo (SSD) and a novel anology between quantum mechanical tunneling and the generation of…

Astrophysics · Physics 2007-05-23 Kandaswamy Subramanian

The standard magnetohydrodynamic (MHD) description of the plasma in the hot, magnetized gas of the intra-cluster (ICM) medium is not adequate because it is weakly collisional. In such collisionless magnetized gas, the microscopic velocity…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 R. Santos-Lima , E. M. de Gouveia Dal Pino , A. Lazarian , G. Kowal , D. Falceta-Gonçalves

We study a simple magnetohydrodynamical approach in which hydrodynamics and MHD turbulence are coupled in a shell model, with given dynamo constrains in the large scales. We consider the case of a low Prandtl number fluid for which the…

Earth and Planetary Astrophysics · Physics 2015-05-13 Roberto Benzi , Jean-Francois Pinton

Recent MHD dynamo simulations for magnetic Prandtl number $>1$ demonstrate that when MHD turbulence is forced with sufficient kinetic helicity, the saturated magnetic energy spectrum evolves from having a single peak below the forcing scale…

Astrophysics · Physics 2009-11-07 Eric G. Blackman

In weakly collisional astrophysical plasmas, such as the intracluster medium of galaxy clusters, the amplification of cosmic magnetic fields by chaotic fluid motions is hampered by the adiabatic production of magnetic-field-aligned pressure…

Plasma Physics · Physics 2019-12-25 Denis A. St-Onge

Magnetic reconnection requires, at least locally, a non-ideal plasma response. In collisionless space and astrophysical plasmas, turbulence could permit this instead of the too rare binary collisions. We investigated the influence of…

Plasma Physics · Physics 2016-05-25 Fabien Widmer , Jörg Büchner , Nobumitsu Yokoi

We investigate the dynamo problem in the limit of small magnetic Prandtl number ($\Pm$) using a shell model of magnetohydrodynamic turbulence. The model is designed to satisfy conservation laws of total energy, cross helicity and magnetic…

Fluid Dynamics · Physics 2007-05-23 Rodion Stepanov , Franck Plunian

This paper studies the nonlinear evolution of magnetic field turbulence in proximity of steady ideal MHD configurations characterized by a small electric current, a small plasma flow, and approximate flux surfaces, a physical setting that…

Plasma Physics · Physics 2024-09-12 Naoki Sato , Michio Yamada

In weakly collisional extragalactic plasmas such as the intracluster medium, viscous stress and the rate of change of the magnetic-field strength are proportional to the local pressure anisotropy, so subject to constraints imposed by the…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-26 Federico Mogavero , Alexander A. Schekochihin

We perform fully kinetic simulations of flows known to produce dynamo in magnetohydrodynamics (MHD), considering scenarios with low Reynolds number and high magnetic Prandtl number, relevant for galaxy cluster scale fluctuation dynamos. We…

The plasmoid instability may lead to fast magnetic reconnection through long current sheets(CS). It is well known that large-Reynolds-number plasmas easily become turbulent. We address the question whether turbulence enhances the energy…

Plasma Physics · Physics 2016-05-03 Fabien Widmer , Jörg Büchner , Nobumitsu Yokoi

We investigate properties of plasma turbulence from magneto-hydrodynamic (MHD) to sub-ion scales by means of two-dimensional, high-resolution hybrid particle-in-cell simulations. We impose an initial ambient magnetic field, perpendicular to…

Solar and Stellar Astrophysics · Physics 2015-10-14 Luca Franci , Simone Landi , Lorenzo Matteini , Andrea Verdini , Petr Hellinger

We present an MHD shell model suitable for computation of various energy fluxes of magnetohydrodynamic turbulence for very small and very large magnetic Prandtl numbers $\mathrm{Pm}$; such computations are inaccessible to direct numerical…

Fluid Dynamics · Physics 2016-09-21 Mahendra K. Verma , Rohit Kumar

Direct numerical simulations of turbulent Hall dynamos are presented. The evolution of an initially weak and small scale magnetic field in a system maintained in a stationary turbulent regime by a stirring force at a macroscopic scale is…

Astrophysics · Physics 2009-11-10 P. D. Mininni , D. O. Gómez , S. M. Mahajan

The free decay of MHD turbulence at large Reynolds numbers is studied numerically using a shell model. We study the statistical properties based on representative sample of realisations (128 realisations for each type of initial conditions)…

Fluid Dynamics · Physics 2010-09-23 Peter Frick , Rodion Stepanov

Isotropic homogeneous hydromagnetic turbulence is studied using numerical simulations at resolutions of up to 1024^3 meshpoints. It is argued that, in contrast to the kinematic regime, the nonlinear regime is characterized by a spectral…

Astrophysics · Physics 2007-05-23 A. Brandenburg , N. E. L. Haugen , W. Dobler

Magnetohydrodynamical (MHD) dynamos emerge in many different astrophysical situations where turbulence is present, but the interaction between large-scale (LSD) and small-scale dynamos (SSD) is not fully understood. We performed a…

Supersonic magnetohydrodynamic (MHD) turbulence is a ubiquitous state for many astrophysical plasmas. However, even the basic statistics for this type of turbulence remains uncertain. We present results from supersonic MHD turbulence…

Astrophysics of Galaxies · Physics 2024-05-31 James R. Beattie , Christoph Federrath , Ralf S. Klessen , Salvatore Cielo , Amitava Bhattacharjee

A variety of studies of magnetised plasma turbulence invoke theories for the advection of a passive scalar by turbulent fluctuations. Examples include modelling the electron density fluctuations in the interstellar medium, understanding the…

Plasma Physics · Physics 2015-06-23 Joanne Mason , Stanislav Boldyrev , Fausto Cattaneo , Jean Carlos Perez