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Related papers: Waves, Coriolis force and the dynamo effect

200 papers

The turbulent diffusion tensor describing the evolution of the mean concentration of a passive scalar is investigated for non-helically forced turbulence in the presence of rotation or a magnetic field. With rotation, the Coriolis force…

Solar and Stellar Astrophysics · Physics 2009-05-09 Axel Brandenburg , Andreas Svedin , Geoffrey M. Vasil

It is shown that the magnetic current-driven (`kink-type') instability produces flow and field patterns with helicity and even with \alpha-effect but only if the magnetic background field possesses non-vanishing current helicity…

Solar and Stellar Astrophysics · Physics 2015-05-20 Guenther Ruediger , Marcus Gellert , Rainer Arlt

We present an implementation of the Hall term in the non-ideal magnetohydrodynamics equations into the adaptive-mesh-refinement code RAMSES to study its impact on star formation. Recent works show that the Hall effect heavily influences the…

Solar and Stellar Astrophysics · Physics 2018-10-31 Pierre Marchand , Benoît Commerçon , Gilles Chabrier

This article presents a calculation of the mean electromotive force arising from general small-scale magnetohydrodynamical turbulence, within the framework of the second-order correlation approximation. With the goal of improving…

High Energy Astrophysical Phenomena · Physics 2015-11-23 Jonathan Squire , Amitava Bhattacharjee

This is the third in a series of papers that deal with angular momentum transport by internal gravity waves. We concentrate on the waves excited by core convection in a 3Msun, Pop I main sequence star. Here, we want to examine the role of…

Astrophysics · Physics 2009-11-13 Florian P. Pantillon , Suzanne Talon , Corinne Charbonnel

To understand the dynamo driven by time-dependent flow, e.g. turbulence, we investigate numerically the dynamo induced by time-periodic force in rotating magnetohydrodynamic flow and focus on the effect of force frequency on the dynamo…

Fluid Dynamics · Physics 2018-03-14 Xing Wei

The effect of magnetic field diffusion on the stability of accretion disks is a problem that has attracted considerable interest of late. In particular, the Hall effect has the potential to bring about remarkable changes in the dynamical…

Earth and Planetary Astrophysics · Physics 2017-03-29 Gopakumar Mohandas , Martin E. Pessah

To elucidate the influence of shear flow on the generation of magnetic field (the dynamo effect), we study the kinematic limit where the magnetic field does not backreact on the velocity field. By non-perturbatively incorporating the effect…

Fluid Dynamics · Physics 2009-07-09 Nicolas Leprovost , Eun-Jin Kim

Intense spin-down flows allow one to reach high Rm in relatively small laboratory setups using moderate mass of liquid metals. The spin-down flow in toroidal channels was the first flow configuration used for studying dynamo effects in…

Fluid Dynamics · Physics 2017-09-26 Peter Frick , Irina Mizeva

Helical magnetic background fields with adjustable pitch angle are imposed on a conducting fluid in a differentially rotating cylindrical container. The small-scale kinetic and current helicities are calculated for various field geometries,…

Solar and Stellar Astrophysics · Physics 2015-05-20 M. Gellert , G. Ruediger , R. Hollerbach

Spatial maps of the high-pass frequency filtered time-averaged root-mean-squared (RMS) Doppler velocities tend to show substantial decrements within regions of strong field and curiously, randomly distributed patches of enhancement in the…

Solar and Stellar Astrophysics · Physics 2015-05-13 Shravan M. Hanasoge

We analyze the effect of the Hall term in the magnetohydrodynamic turbulence under a strong externally supported magnetic field, seeing how this changes the energy cascade, the characteristic scales of the flow and the dynamics of global…

Plasma Physics · Physics 2012-05-21 L. N. Martin , P. Dmitruk , D. O. Gomez

The large abundance of electrically neutral particles has a remarkable impact on the dynamics of many astrophysical plasmas. Here, we use a two-fluid model that includes charge-neutral elastic collisions and Hall's current to study the…

Solar and Stellar Astrophysics · Physics 2025-02-20 David Martínez-Gómez

In this paper, we report an interesting kinematic phenomenon around the halos' edge related to the splashback radius. After the shell-crossing, cosmic flow exhibits various rotational morphologies via stream-mixing. Vorticity is generated…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-07 Xiaolin Luo , Xiangling Xu , Xin Wang

A detailed study of small-scale Hall magnetohydrodynamic dynamo has been performed both analytically and numerically. Assuming the magnetic field and the current to be separate fields, the contribution of the Hall term has been decomposed…

Fluid Dynamics · Physics 2023-06-01 Arijit Halder , Supratik Banerjee , Anando G. Chatterjee , Manohar K. Sharma

The role of turbulence in astrophysical environments and its interplay with magnetic fields is still highly debated. In this lecture, we will discuss this issue in the framework of dynamo processes. We will first present a very brief…

Solar and Stellar Astrophysics · Physics 2015-06-12 E. M. de Gouveia Dal Pino , R. Santos-Lima , G. Kowal , D. Falceta-Gonçalves

Numerical simulations of forced turbulence in elongated shearing boxes are carried out to demonstrate that a nonhelical turbulence in conjunction with a linear shear can give rise to a mean-field dynamo. Exponential growth of magnetic field…

Intra-cell motion endows rich non-trivial phenomena to a wide variety of quantum materials. The most prominent example is a transverse current in the absence of a magnetic field (i.e. the anomalous Hall effect). Here we show that, in…

Mesoscale and Nanoscale Physics · Physics 2020-01-15 Eddwi H. Hasdeo , Alex J. Frenzel , Justin C. W. Song

We review mechanisms for the transport of angular momentum in accretion disks that are low mass, in the sense that the gravitational forces produced by the material in these disks has a negligible effect on disk dynamics. There is no…

Astrophysics · Physics 2007-05-23 ET Vishniac , PH Diamond

Using a 1-MA, 100ns-rise-time pulsed power generator, radial foil configurations can produce strongly collimated plasma jets. The resulting jets have electron densities on the order of 10^20 cm^-3, temperatures above 50 eV and plasma…

Plasma Physics · Physics 2013-01-07 P. -A. Gourdain , C. E. Seyler