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We analyze probe data obtained from a toroidal magnetized plasma configuration suitable for studies of low-frequency gradient-driven instabilities. These instabilities give rise to field-aligned convection rolls analogous to Rayleigh-Benard…

Plasma Physics · Physics 2009-11-13 Tatjana Zivkovic , Kristoffer Rypdal

We analyze the initial, kinematic stage of magnetic field evolution in an isotropic and homogeneous turbulent conducting fluid with a rough velocity field, v(l) ~ l^alpha, alpha<1. We propose that in the limit of small magnetic Prandtl…

Astrophysics · Physics 2007-05-23 Stanislav Boldyrev , Fausto Cattaneo

In rapidly rotating turbulence (Rossby number much less than unity), the standard mixing length theory for turbulent convection breaks and Coriolis force enters the force balance such that magnetic field eventually depends on rotation. By…

Solar and Stellar Astrophysics · Physics 2022-02-16 Xing Wei

The planar quantum dynamics of a neutral particle with a magnetic dipole moment in the presence of electric and magnetic fields is considered. The criteria to establish the planar dynamics reveal that the resulting nonrelativistic…

High Energy Physics - Theory · Physics 2014-12-09 Edilberto O. Silva

Small-scale dynamos play important roles in modern astrophysics, especially on Galactic and extragalactic scales. Owing to dynamo action, purely hydrodynamic Kolmogorov turbulence hardly exists and is often replaced by hydromagnetic…

Astrophysics of Galaxies · Physics 2022-12-20 A. Brandenburg , I. Rogachevskii , J. Schober

Using simulations of helically driven turbulence, it is shown that the ratio of kinetic to magnetic energy dissipation scales with the magnetic Prandtl number in power law fashion with an exponent of approximately 0.6. Over six orders of…

Solar and Stellar Astrophysics · Physics 2011-05-16 A. Brandenburg

The small-scale turbulent dynamo in the high Prandtl number regime is described in terms of the one-point Fourier space correlators. The second order correlator of this kind is the energy spectrum and it has been previously studied in…

Astrophysics · Physics 2009-11-07 S. Nazarenko , R. J. West , O. Zaboronski

We report an extensive numerical study of the small-scale turbulent dynamo at large magnetic Prandtl numbers Pm. A Pm scan is given for the model case of low-Reynolds-number turbulence. We concentrate on three topics: magnetic-energy…

Astrophysics · Physics 2008-11-26 A. A. Schekochihin , S. C. Cowley , S. F. Taylor , J. L. Maron , J. C. McWilliams

Using the conventional approach of superposing plane waves, it is not possible to create a strictly isotropic turbulent magnetic field structure that obeys all physical constraints, which are (i) equal mean of all magnetic field components;…

Computational Physics · Physics 2013-06-17 R. C. Tautz

Fluctuation dynamo action has been obtained for a flow previously used to model fluid turbulence, where the sensitivity of the magnetic field parameters to the kinetic energy spectrum can be explored. We apply quantitative morphology…

Astrophysics · Physics 2008-11-26 S. Louise Wilkin , Carlo F. Barenghi , Anvar Shukurov

Active and passive scalars transported by an incompressible two-dimensional conductive fluid are investigated. It is shown that a passive scalar displays a direct cascade towards the small scales while the active magnetic potential builds…

Chaotic Dynamics · Physics 2009-11-07 A. Celani , M. Cencini , A. Mazzino , M. Vergassola

Nonthermal scaling phenomena can exhibit a characteristic dependence on the dimensionality d of space. For d=3 and 4 we simulate a relativistic scalar field theory on a lattice and compute turbulent scaling exponents. We recover Kolmogorov…

High Energy Physics - Phenomenology · Physics 2011-04-22 J. Berges , D. Sexty

The small-scale dynamo provides a highly efficient mechanism for the conversion of turbulent into magnetic energy. In astrophysical environments, such turbulence often occurs at high Mach numbers, implying steep slopes in the turbulent…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Stefano Bovino , Dominik R. G. Schleicher , Jennifer Schober

Particle-laden turbulence involves complex interactions between the dispersed and continuous phases. Given that particles can exhibit a wide range of properties, such as varying density, size, and shape, their interplay with the flow can…

We investigate the structure of magnetic field amplified by turbulent velocity fluctuations, in the framework of the kinematic Kazantsev-Kraichnan model. We consider Kolmogorov distribution of velocity fluctuations, and assume that both…

Astrophysics · Physics 2010-01-15 Leonid Malyshkin , Stanislav Boldyrev

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

(Abridged) The small-scale dynamo may play a substantial role in magnetizing the Universe under a large range of conditions, including subsonic turbulence at low Mach numbers, highly supersonic turbulence at high Mach numbers and a large…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Dominik R. G. Schleicher , Jennifer Schober , Christoph Federrath , Stefano Bovino , Wolfram Schmidt

This paper provides a brief overview of dynamo scaling relationships for the degree of equipartition between magnetic and kinetic energies. Three basic approaches are adopted to explore these scaling relationships, with a first look at two…

Solar and Stellar Astrophysics · Physics 2017-01-11 Kyle Augustson , Stéphane Mathis , Allan Sacha Brun

We have tested the ability of driven turbulence to generate magnetic field structure from a weak uniform field using three dimensional numerical simulations of incompressible turbulence. We used a pseudo-spectral code with a numerical…

Astrophysics · Physics 2009-10-31 Jungyeon Cho , Ethan T. Vishniac

We simulate the evolution of an initially weak magnetic field in forced turbulence for a range of Prandtl numbers. The field grows exponentially with the Kulsrud-Anderson $k^{3/2}$ spectrum until the magnetic energy approaches the…

Astrophysics · Physics 2009-09-25 Jason Maron , Steven Cowley