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Related papers: Small-scale-field Dynamo

200 papers

We study the amplification of magnetic fields during the formation of primordial halos. The turbulence generated by gravitational infall motions during the formation of the first stars and galaxies can amplify magnetic fields very…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Jennifer Schober , Dominik Schleicher , Christoph Federrath , Simon Glover , Ralf Klessen , Robi Banerjee

Radiative diagnostics of high-energy density plasmas is addressed in this paper. We propose that the radiation produced by energetic particles in small-scale magnetic field turbulence, which can occur in laser-plasma experiments,…

Plasma Physics · Physics 2015-05-28 Sarah J. Reynolds , Mikhail V. Medvedev

Magnetic fields grow quickly, even at early cosmological times, suggesting the action of a small-scale dynamo (SSD) in the interstellar medium (ISM) of galaxies. Many studies have focused on idealized, isotropic, homogeneous, turbulent…

Astrophysics of Galaxies · Physics 2023-02-15 Frederick A. Gent , Mordecai-Mark Mac Low , Maarit J. Korpi-Lagg , Nishant K. Singh

In this paper, we study the development of anisotropy in strong MHD turbulence in the presence of a large scale magnetic field B 0 by analyzing the results of direct numerical simulations. Our results show that the developed anisotropy…

Plasma Physics · Physics 2017-06-14 Sita Sundar , Mahendra K. Verma , Alexandros Alexakis , Anando G. Chatterjee

The stability of a sheared magnetic field is analyzed in two-dimensional magnetohydrodynamics with resistive and viscous dissipation. Using a multiple-scale analysis, it is shown that at large enough Reynolds numbers the basic state…

chao-dyn · Physics 2007-05-23 G. Boffetta , A. Celani , R. Prandi

Additional physics beyond standard hydrodynamics is needed to fully model the intracluster medium (ICM); however, as we move to more sophisticated models, it is important to consider the role of magnetic fields and the way the fluid…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-04 Hilary Egan , Brian W. O'Shea , Eric Hallman , Jack Burns , Hao Xu , David Collins , Hui Li , Michael L. Norman

We study the evolution of an inflation-generated magnetic field, due to its coupling to fluid motions, during cosmological phase transitions. We find that the magnetic field stays almost unchanged on large scales, while on small scales the…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Tina Kahniashvili , Axel Brandenburg , Leonardo Campanelli , Bharat Ratra , Alexander G. Tevzadze

Saturated small-scale dynamo solutions driven by isotropic non-helical turbulence are presented at low magnetic Prandtl numbers Pm down to 0.01. For Pm < 0.1, most of the energy is dissipated via Joule heat and, in agreement with earlier…

Solar and Stellar Astrophysics · Physics 2011-10-25 Axel Brandenburg

An axisymmetric magnetic field is applied to a spherical, turbulent flow of liquid sodium. An induced magnetic dipole moment is measured which cannot be generated by the interaction of the axisymmetric mean flow with the applied field,…

Plasma Physics · Physics 2007-05-23 E. J. Spence , M. D. Nornberg , C. M. Jacobson , R. D. Kendrick , C. B. Forest

Small-scale turbulent dynamo is responsible for the amplification of magnetic fields on scales smaller than the driving scale of turbulence in diverse astrophysical media. Most earlier dynamo theories concern the kinematic regime and…

Astrophysics of Galaxies · Physics 2021-06-25 Siyao Xu , Alex Lazarian

Magnetic fields are present on all scales in the Universe. While we understand the processes which amplify the fields fairly well, we do not have a "natural" mechanism to generate the small initial seed fields. By using fully relativistic…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-18 Ellie Nalson , Adam J. Christopherson , Karim A. Malik

Magnetic field generation on scales large compared with the scale of the turbulent eddies is known to be possible via the so-called $\alpha$ effect when the turbulence is helical and if the domain is large enough for the $\alpha$ effect to…

Solar and Stellar Astrophysics · Physics 2013-11-18 Simon Candelaresi , Axel Brandenburg

Magnetic field generation in three-dimensional Rayleigh-B\'enard convection of an electrically conducting fluid is studied numerically by fixing the Prandtl number at $P=0.3$ and varying the Rayleigh number (Ra) as a control parameter. A…

Fluid Dynamics · Physics 2017-10-11 R. Chertovskih , E. L. Rempel , E. V. Chimanski

Magnetic fields pervade the entire Universe and affect the formation and evolution of astrophysical systems from cosmological to planetary scales. The generation and dynamical amplification of extragalactic magnetic fields through cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-27 F. Rincon , F. Califano , A. A. Schekochihin , F. Valentini

We present results from the first 3D kinetic numerical simulation of magnetorotational turbulence and dynamo, using the local shearing-box model of a collisionless accretion disc. The kinetic magnetorotational instability grows from a…

High Energy Astrophysical Phenomena · Physics 2016-12-07 Matthew W. Kunz , James M. Stone , Eliot Quataert

Context: During the last decades, significant progress has been made in both numerical simulations of turbulent dynamo and theoretical understanding of turbulence. However, there is still lack of quantitative comparison between the…

Fluid Dynamics · Physics 2026-04-08 A. V. Kopyev , A. S. Il'yn , V. A. Sirota , K. P. Zybin

Using direct numerical simulations (DNS) we verify that in the kinematic regime, a turbulent helical dynamo grows in such a way that the magnetic energy spectrum remains to high precision shape-invariant, i.e., at each wavenumber $k$ the…

Astrophysics of Galaxies · Physics 2014-10-24 Kandaswamy Subramanian , Axel Brandenburg

Using numerical simulations of forced turbulence, it is shown that for magnetic Reynolds numbers larger than unity, i.e., beyond the regime of quasilinear theory, the turbulent magnetic diffusivity attains an additional negative…

Fluid Dynamics · Physics 2017-10-03 A. Brandenburg , J. Schober , I. Rogachevskii

We address magnetic-field generation by dynamo action in systems with inhomogeneous electrical conductivity and magnetic permeability. More specifically, we first show that the Taylor-Couette kinematic dynamo undergoes a drastic reduction…

Fluid Dynamics · Physics 2021-12-29 Florence Marcotte , Basile Gallet , Francois Pétrélis , Christophe Gissinger

Using the linear fractional transformation, connecting effective conductivities sigma_{e} of isotropic two-phase systems with and without magnetic field, explicit approximate expressions for sigma_{e} in a magnetic field are obtained. They…

Disordered Systems and Neural Networks · Physics 2009-11-10 S. A. Bulgadaev , F. V. Kusmartsev