English
Related papers

Related papers: Negative Turbulent Magnetic Diffusivity $\beta$ ef…

200 papers

We present a 2.5D MHD simulation of a magnetic flux rope (FR) propagating in the heliosphere and investigate the cause of the observed sharp plasma beta transition. Specifically, we consider a strong internal magnetic field and an explosive…

Solar and Stellar Astrophysics · Physics 2015-06-17 Neel P. Savani , A. Vourlidas , D. Shiota , M. G. Linton , K. Kusano , N. Lugaz , A. P. Rouillard

The question of whether a dynamo can be triggered by gravitational collapse is of great interest, especially for the early Universe. Here, we employ supercomoving coordinates to study the magnetic field amplification from decaying…

Astrophysics of Galaxies · Physics 2025-09-11 Axel Brandenburg , Evangelia Ntormousi

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

Supernovae are the dominant energy source for driving turbulence within the interstellar plasma. Until recently, their effects on magnetic field amplification in disk galaxies remained a matter of speculation. By means of self-consistent…

Astrophysics · Physics 2009-11-13 Oliver Gressel , Udo Ziegler , Detlef Elstner , Günther Rüdiger

The nonlinear dynamics of magnetic helicity, $H^M$, which is responsible for large-scale magnetic structure formation in electrically conducting turbulent media is investigated in forced and decaying three-dimensional magnetohydrodynamic…

Fluid Dynamics · Physics 2015-06-03 Wolf-Christian Müller , Shiva Kumar Malapaka , Angela Busse

We have performed extensive two-dimensional magnetohydrodynamic simulations to study the amplification of magnetic fields when a supernova blast wave propagates into a turbulent interstellar plasma. The blast wave is driven by injecting…

High Energy Astrophysical Phenomena · Physics 2015-06-03 Fan Guo , Shengtai Li , Hui Li , Joe Giacalone , J. R. Jokipii , David Li

Employing the standard solar interior model as input we construct a dynamically-consistent nonlinear dynamo model that takes into account the detailed description of the \Lambda- effect, turbulent pumping, magnetic helicity balance, and…

Solar and Stellar Astrophysics · Physics 2018-07-31 V. V. Pipin

The turbulent magnetic diffusivity tensor is determined in the presence of rotation or shear. The question is addressed whether dynamo action from the shear-current effect can explain large-scale magnetic field generation found in…

Astrophysics · Physics 2010-11-05 A. Brandenburg , K. -H. Rädler , M. Rheinhardt , P. J. Käpylä

The turbulent dynamo may explain the origin of cosmic magnetism. While the exponential amplification of magnetic fields has been studied for incompressible gases, little is known about dynamo action in highly-compressible, supersonic…

Astrophysics of Galaxies · Physics 2014-12-05 Christoph Federrath , Jennifer Schober , Stefano Bovino , Dominik R. G. Schleicher

Context: Most solar and stellar dynamo models use the alpha-Omega scenario where the magnetic field is generated by the interplay between differential rotation (the Omega effect) and a mean electromotive force due to helical turbulent…

Solar and Stellar Astrophysics · Physics 2009-12-08 N. Seehafer , V. V. Pipin

The magnetohydrodynamic (MHD) description of plasmas with relativistic particles necessarily includes an additional new field, the chiral chemical potential associated with the axial charge (i.e., the number difference between right- and…

We study of the effect of turbulence on diffusion processes within magnetized medium. While we exemplify our treatment with heat transfer processes, our results are quite general and are applicable to different processes, e.g. diffusion of…

Astrophysics · Physics 2008-11-26 Alex Lazarian

We perform kinematic simulations of dynamo action driven by a helical small scale flow of a conducting fluid in order to deduce mean-field properties of the combined induction action of small scale eddies. We examine two different flow…

Fluid Dynamics · Physics 2014-07-28 Andre Giesecke , Frank Stefani , Gunter Gerbeth

Results from a numerical study of fluctuation dynamo in a collisionless, weakly magnetized plasma are presented. The key difference between this dynamo and its magnetohydrodynamic (MHD) counterpart is the adiabatic production of…

High Energy Astrophysical Phenomena · Physics 2018-08-17 Denis A. St-Onge , Matthew W. Kunz

We discuss the model of magnetic field reconnection in the presence of turbulence introduced by us approximately ten years ago. The model does not require any plasma effects to be involved in order to make the reconnection fast. In fact, it…

Astrophysics · Physics 2008-12-13 A. Lazarian , E. Vishniac

In this work the influence of the chiral anomaly effect on the evolution of magnetohydrodynamic turbulence was studied. We argue that in the early universe, before the electroweak symmetry breaking, and for temperatures high enough such…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-12 Petar Pavlović , Natacha Leite , Günter Sigl

Plasma beta is an important and fundamental physical quantity in order to understand plasma dynamics, particularly in the context of magnetically active stars, because it tells about the domination of magnetic versus thermodynamic processes…

Solar and Stellar Astrophysics · Physics 2017-11-30 Philippe-A. Bourdin

The amplification of magnetic fields is crucial for understanding the observed magnetization of stars and galaxies. Turbulent dynamo is the primary mechanism responsible for that but the understanding of its action in a collapsing…

Astrophysics of Galaxies · Physics 2026-04-22 Muhammed Irshad P , Pallavi Bhat , Kandaswamy Subramanian , Anvar Shukurov

The irregular polarity reversals of the Earth's magnetic field have attracted much interest during the last decades. Despite the fact that recent numerical simulations of the geodynamo have shown nice polarity transitions, the very reason…

Geophysics · Physics 2007-05-23 F. Stefani , G. Gerbeth , U. Guenther

In magnetized, stratified astrophysical environments such as the Sun's corona and solar wind, Alfv\'enic fluctuations ''reflect'' from background gradients, enabling nonlinear interactions and thus dissipation of their energy into heat.…

Solar and Stellar Astrophysics · Physics 2023-08-22 Romain Meyrand , Jonathan Squire , Alfred Mallet , Benjamin D. G. Chandran
‹ Prev 1 8 9 10 Next ›