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Related papers: Waves, Coriolis force and the dynamo effect

200 papers

We use three-dimensional direct numerical simulations of the helically forced magnetohydrodynamic equations in spherical shell segments in order to study the effects of changes in the geometrical shape and size of the domain on the growth…

Astrophysics · Physics 2010-01-15 Dhrubaditya Mitra , Reza Tavakol , Axel Brandenburg , David Moss

The current understanding of astrophysical magnetic fields is reviewed, focusing on their generation and maintenance by turbulence. In the astrophysical context this generation is usually explained by a self-excited dynamo, which involves…

Astrophysics · Physics 2008-11-26 Axel Brandenburg , Kandaswamy Subramanian

We consider the quantum Hall effect induced by magnetic field and rotation, which can drive the Hall samples into the quantum Hall regime and induce fractional excitations. Both the mass and the charge of the Laughlin quasiparticles are…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Bo Zhao , Zeng-Bing Chen

Inertial effects play an important role in classical mechanics but have been largely overlooked in quantum mechanics. Nevertheless, the analogy between inertial forces on mass particles and electromagnetic forces on charged particles is not…

Mesoscale and Nanoscale Physics · Physics 2015-03-03 Julio E. Brandão , F. Moraes , M. M. Cunha , Jonas R. F. Lima , C. Filgueiras

The solar surface dynamo has become an active area of research in an attempt to understand the origin of a variety of magnetic field structures on the sun. The major modification that needs to be incorporated in the standard dynamo process…

Solar and Stellar Astrophysics · Physics 2009-03-23 V. Krishan

Kinetic helicity is a fundamental characteristics of astrophysical turbulent flows. It is not only responsible for the generation of large-scale magnetic fields in the Sun, stars, and spiral galaxies, but it also affects turbulent diffusion…

Fluid Dynamics · Physics 2025-05-15 Igor Rogachevskii , Nathan Kleeorin , Axel Brandenburg

The magnetic field due to an axially symmetric, hot and highly conducting plasma, taken as an ideal magnetohydrodynamic fluid, surrounding a slow rotating compact gravitational object is studied within the context of Einstein-Maxwell field…

General Relativity and Quantum Cosmology · Physics 2017-10-02 Babur M. Mirza

Planetary and stellar magnetic fields are thought to be sustained by helical motions ($\alpha$-effect) and, if present, differential rotation ($\Omega$-effect). In the Sun, the strong differential rotation in the tachocline is responsible…

Earth and Planetary Astrophysics · Physics 2014-02-04 Wieland Dietrich , Dieter Schmitt , Johannes Wicht

This paper is devoted to the study of water waves under the influence of the gravity and the Coriolis force. It is quite common in the physical literature that the rotating shallow water equations are used to study such water waves. We…

Analysis of PDEs · Mathematics 2016-09-12 Benjamin Melinand

Understanding the in situ amplification of large scale magnetic fields in turbulent astrophysical rotators has been a core subject of dynamo theory. When turbulent velocities are helical, large scale dynamos that substantially amplify…

Fluid Dynamics · Physics 2012-06-22 Jonathan Pietarila Graham , Eric G. Blackman , Pablo D. Mininni , Annick Pouquet

The constraint imposed by magnetic helicity conservation on the alpha effect is considered for both magnetically and flow dominated self-organizing plasmas. Direct numerical simulations are presented for a dominant contribution to the alpha…

High Energy Astrophysical Phenomena · Physics 2015-06-18 F. Ebrahimi , A. Bhattacharjee

Magnetic fields play an important role in star formation by regulating the removal of angular momentum from collapsing molecular cloud cores. Hall diffusion is known to be important to the magnetic field behaviour at many of the…

Solar and Stellar Astrophysics · Physics 2011-10-12 Catherine Braiding

The dynamo equations are solved numerically with a helical forcing corresponding to the Roberts flow. In the fully turbulent regime the flow behaves as a Roberts flow on long time scales, plus turbulent fluctuations at short time scales.…

Fluid Dynamics · Physics 2020-04-24 Yannick Ponty , Franck Plunian

We study the linear theory of magnetohydrodynamic (MHD) waves, namely the Alfv{\'e}n and the fast and slow magnetosonic modes in a rotating Hall-MHD plasma with the effects of the obliqueness of the external magnetic field and the Coriolis…

Plasma Physics · Physics 2025-06-16 A. P. Misra , R. Dey , V. Krishan

The role of the Hall term on large scale dynamo action is investigated by means of the First Order Smoothing Approximation. It is shown that the standard $\alpha$ coefficient is altered, and is zero when a specific double Beltrami state is…

Astrophysics of Galaxies · Physics 2016-09-28 Manasvi Lingam , Amitava Bhattacharjee

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…

The "reverse-dynamo" mechanism - the amplification/generation of fast plasma flows by micro scale (turbulent) magnetic fields via magneto-fluid coupling is recognized and explored. It is shown that macro-scale magnetic fields and flows are…

Spiral galaxies host dynamically important magnetic fields which can affect gas flows in the disks and halos. Total magnetic fields in spiral galaxies are strongest (up to 30 \muG) in the spiral arms where they are mostly turbulent or…

Astrophysics · Physics 2009-06-23 Rainer Beck

A new type of anomalous Hall effect is shown to arise from the interaction of conduction electrons with dipolar spin waves in ferromagnets. This effect exists even in homogeneous ferromagnets without relativistic spin-orbit coupling. The…

Materials Science · Physics 2015-10-14 Kei Yamamoto , Koji Sato , Eiji Saitoh , Hiroshi Kohno

In many astrophysical environments, self-gravity can generate kinetic energy, which, in principle, is available for driving dynamo action. Using direct numerical simulations, we show that in unstirred self-gravitating subsonic turbulence…

Astrophysics of Galaxies · Physics 2022-04-20 Axel Brandenburg , Evangelia Ntormousi