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Related papers: Magnetic stochasticity and diffusion

200 papers

Kinematic dynamo in incompressible isotropic turbulent flows with high magnetic Prandtl number is considered. The approach interpreting an arbitrary magnetic field distribution as a superposition of localized perturbations (blobs) is…

Fluid Dynamics · Physics 2023-10-26 A. S. Il'yn , A. V. Kopyev , V. A. Sirota , K. P. Zybin

Turbulence is believed to play important roles in the origin of cosmic magnetism. While it is well known that turbulence can efficiently amplify a uniform or spatially homogeneous seed magnetic field, it is not clear whether or not we can…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Jungyeon Cho

The origin of strong magnetic fields in the Universe can be explained by amplifying weak seed fields via turbulent motions on small spatial scales and subsequently transporting the magnetic energy to larger scales. This process is known as…

Local magnetic reversals are an inseparable part of magnetohydrodynamic (MHD) turbulence whose collective outcome on an arbitrary scale in the inertial range may lead to a global stochastic reconnection event with a rate independent of…

High Energy Astrophysical Phenomena · Physics 2021-01-20 Amir Jafari , Ethan Vishniac , Siyao Xu

We test a new technique of studying magnetohydrodynamic (MHD) turbulence suggested by Lazarian \& Pogosyan, using synthetic synchrotron polarization observations. This paper focuses on a one-point statistics, which is termed the…

High Energy Astrophysical Phenomena · Physics 2016-07-20 Jian-Fu Zhang , Alex Lazarian , Hyeseung Lee , Jungyeon Cho

We study a nonlinear quenching of turbulent magnetic diffusion and effective drift velocity of large-scale magnetic field in a developed two-dimensional MHD turbulence at large magnetic Reynolds numbers. We show that transport of the…

Astrophysics · Physics 2009-06-23 N. Kleeorin , I. Rogachevskii

A non-perturbative nonlinear statistical approach is presented to describe turbulent magnetic systems embedded in a uniform mean magnetic field. A general formula in the form of an ordinary differential equation for magnetic field-line…

Astrophysics · Physics 2009-11-13 A. Shalchi , I. Kourakis

In astrophysics, turbulent diffusion is often used in place of microphysical diffusion to avoid resolving the small scales. However, we expect this approach to break down when time and length scales of the turbulence become comparable with…

Solar and Stellar Astrophysics · Physics 2014-09-05 M. S. Väisälä , A. Brandenburg , Dhrubaditya Mitra , P. J. Käpylä , M. J. Mantere

We model chaotic diffusion, in a symplectic 4D map by using the result of a theorem that was developed for stochastically perturbed integrable Hamiltonian systems. We explicitly consider a map defined by a free rotator (FR) coupled to a…

Chaotic Dynamics · Physics 2015-06-17 Martín F. Mestre , Armando Bazzani , Pablo M. Cincotta , Claudia M. Giordano

We consider potential type dynamical systems in finite dimensions with two meta-stable states. They are subject to two sources of perturbation: a slow external periodic perturbation of period $T$ and a small Gaussian random perturbation of…

Probability · Mathematics 2007-05-23 Samuel Herrmann , Peter Imkeller , Dierk Peithmann

Astrophysical fluids are generically turbulent, which means that frozen-in magnetic fields are, at least, weakly stochastic. Therefore realistic studies of astrophysical magnetic reconnection should include the effects of stochastic…

Astrophysics · Physics 2008-12-31 A. Lazarian , E. Vishniac , G. Kowal

In this paper we present a new model for modeling the diffusion and relative dispersion of particles in homogeneous isotropic turbulence. We use an Heisenberg-like Hamiltonian to incorporate spatial correlations between fluid particles,…

Fluid Dynamics · Physics 2012-12-18 Thomas Burgener , Dirk Kadau , Hans Jürgen Herrmann

Tangled magnetic fields, often coexisting with an ordered mean field, have a major impact on turbulence and momentum transport in many plasmas, including those found in the solar tachocline and magnetic confinement devices. We present a…

Plasma Physics · Physics 2021-04-09 Chang-Chun Chen , Patrick H. Diamond , Rameswar Singh , Steven M. Tobias

Accretion disks are likely threaded by external vertical magnetic flux, which enhances the level of turbulence via the magnetorotational instability (MRI). Using shearing-box simulations, we find that such external magnetic flux also…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Xue-Ning Bai , James M. Stone

The chaotic dynamics of small-scale vorticity plays a key role in understanding and controlling turbulence, with direct implications for energy transfer, mixing, and coherent structure evolution. However, measuring or controlling its…

A wide variety of astrophysical phenomena involve the flow of turbulent magnetized gas with relativistic velocity or energy density. Examples include gamma-ray bursts, active galactic nuclei, pulsars, magnetars, micro-quasars, merging…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Jonathan Zrake , Andrew MacFadyen

The behavior of magnetic field lines in a turbulent plasma is a key property of the medium, with important consequences for plasma dynamics and charged-particle transport. We study the diffusion properties of magnetic field lines in…

High Energy Astrophysical Phenomena · Physics 2026-05-22 Matthieu Bouchet , Yoann Génolini , Silvio S. Cerri , Alexandre Marcowith , Philipp Mertsch

We discuss the effect of stochastic resonance in a simple model of magnetic reversals. The model exhibits statistically stationary solutions and bimodal distribution of the large scale magnetic field. We observe a non trivial amplification…

Chaotic Dynamics · Physics 2015-05-27 Roberto Benzi , Jean-Francois Pinton

Dynamo action owing to helically forced turbulence and large-scale shear is studied using direct numerical simulations. The resulting magnetic field displays propagating wave-like behavior. This behavior can be modelled in terms of an…

Astrophysics · Physics 2011-02-11 P. J. Käpylä , A. Brandenburg

How stochastic, microscopic events generate deterministic, macroscopic properties is a fundamental question in physics. We address this question by developing a quantum master equation model for concentrated radical solutions, where random…

Chemical Physics · Physics 2026-05-26 Yoshiaki Uchida , Ryohei Kishi