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Related papers: On Simplified Numerical Turbulence Models in Test-…

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The diffusive motion of charged particles in synthetic magnetic turbulence with different properties is investigated by using numerical simulations with unprecedented dynamical range, which allow us to ensure that both the inertial range…

High Energy Astrophysical Phenomena · Physics 2020-11-24 Andrej Dundovic , Oreste Pezzi , Pasquale Blasi , Carmelo Evoli , William H. Matthaeus

Using the test-field method for nearly irrotational turbulence driven by spherical expansion waves it is shown that the turbulent magnetic diffusivity increases with magnetic Reynolds numbers. Its value levels off at several times the rms…

Astrophysics of Galaxies · Physics 2010-11-05 Axel Brandenburg , Fabio Del Sordo

This paper presents a method for generating a turbulent velocity field that can be used as an input for the temporal simulation in wind excited structure problems. Temporal simulations become necessary when nonlinear behaviour, in the…

Fluid Dynamics · Physics 2023-12-15 Pascal Hémon , Françoise Santi

New high-resolution observations reveal that small-scale magnetic flux concentrations have a delicate substructure on a spatial scale of 0.1''. Its basic structure can be interpreted in terms of a magnetic flux sheet or tube that vertically…

Astrophysics · Physics 2007-05-23 Oskar Steiner

In interstellar medium studies, separating ordered and random velocity or magnetic fields is essential for interpreting turbulence in both simulations and observations. We investigate how the choice of averaging scale affects the…

Astrophysics of Galaxies · Physics 2026-04-01 A. Konstantinou , E. Ntormousi , K. Tassis

Synthetic turbulence is a relevant tool to study complex astrophysical and space plasma environments inaccessible by direct simulation. However, conventional models lack intermittent coherent structures, which are essential in realistic…

Space Physics · Physics 2024-05-08 Jeremiah Lübke , Frederic Effenberger , Mike Wilbert , Horst Fichtner , Rainer Grauer

Bearing in mind the application to the outer crust of the neutron stars (NSs), we investigate the magnetic field decay by means of the fully relativistic Particle-In-Cell simulations. Numerical computations are carried out in 2-dimensions,…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Hiroyuki R. Takahashi , Kei Kotake , Nobutoshi Yasutake

Motivated by recent simulations of sunspot formation, we extend the theory of the pressure difference between magnetized and non-magnetized gas by Dicke to include rotating turbulence. While the (vertical) background field provides a…

Solar and Stellar Astrophysics · Physics 2018-10-17 M. Küker , G. Rüdiger

Inertial-range features of turbulence are investigated using data from experimental measurements of grid turbulence and direct numerical simulations of isotropic turbulence simulated in a periodic box, both at the Taylor-scale Reynolds…

A higher-order multiscale analysis of spatial anisotropy in inertial range magnetohydrodynamic turbulence is presented using measurements from the STEREO spacecraft in fast ambient solar wind. We show for the first time that, when measuring…

Space Physics · Physics 2014-03-05 K. T. Osman , K. H. Kiyani , S. C. Chapman , B. Hnat

It is well-recognized that the presence of magnetic fields will lead to anisotropic energy cascade and dissipation of astrophysical turbulence. With the diffusion approximation and linear dissipation rates, we study the cascade and damping…

Solar and Stellar Astrophysics · Physics 2009-03-31 Yanwei Jiang , Siming Liu , Vahé Petrosian

We propose a phenomenological model for incompressible magnetohydrodynamic turbulence. We argue that nonlinear-wave interaction weakens as the energy cascade proceeds to small scales, however, the anisotropy of fluctuations along the…

Astrophysics · Physics 2009-11-10 Stanislav Boldyrev

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,…

A simulation study of the magnetic electron drift vortex (MEDV) mode turbulence in a magnetoplasma in the presence of inhomogeneities in the plasma temperature and density, as well as in the external magnetic field, is presented. The study…

Plasma Physics · Physics 2015-05-13 Dastgeer Shaikh , B Eliasson , P K Shukla

Numerical simulations of the propagation of charged particles through magnetic fields solving the equation of motion often leads to the usage of an interpolation in case of discretely defined magnetic fields, typically given on a…

High Energy Astrophysical Phenomena · Physics 2021-07-14 L. Schlegel , A. Frie , B. Eichmann , P. Reichherzer , J. Becker Tjus

Small-scale magnetic turbulence observed by the Cluster spacecraft in the plasma sheet is investigated by means of a wavelet estimator suitable for detecting distinct scaling characteristics even in noisy measurements. The spectral…

Observations of galaxy clusters show that the intracluster medium (ICM) is likely to be turbulent and is certainly magnetized. The properties of this magnetized turbulence are determined both by fundamental nonlinear magnetohydrodynamic…

Astrophysics · Physics 2008-11-26 A. A. Schekochihin , S. C. Cowley

We present an analytic derivation of the temporal dependence of the perpendicular transport coefficient of charged particles in magnetostatic turbulence, for times smaller than the time needed to charged particles to travel the turbulence…

High Energy Astrophysical Phenomena · Physics 2015-05-27 F. Fraschetti , J. R. Jokipii

We present preliminary results from high resolution magneto-convection simulations where we find the formation of flux concentrations from an initially uniform magnetic field. We compute the effective magnetic pressure but find that the…

Solar and Stellar Astrophysics · Physics 2015-12-16 P. J. Käpylä , A. Brandenburg , N. Kleeorin , M. J. Mantere , I. Rogachevskii

The amplification and maintenance of the observed magnetic fields in the ICM are usually attributed to the turbulent dynamo action. This is generally derived employing a collisional MHD model. However, in the ICM the ion mean free path…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 R. Santos-Lima , E. M. de Gouveia Dal Pino , G. Kowal , D. Falceta-Gonçalves , A. Lazarian , M. S. Nakwacki