English
Related papers

Related papers: A two-layer $\alpha\omega$ dynamo model, and its i…

200 papers

Motivated by solid-solid phase transitions in elastic thin films, we perform a Gamma-convergence analysis for a singularly perturbed energy describing second order phase transitions in a domain of vanishing thickness. Under a two-wells…

Analysis of PDEs · Mathematics 2012-02-29 Bernardo Galvão-Sousa , Vincent Millot

We examine kinematic dynamo action driven by an axisymmetric large scale flow that is superimposed with an azimuthally propagating non-axisymmetric perturbation with a frequency $\omega$. Although we apply a rather simple large scale…

Fluid Dynamics · Physics 2017-05-23 Andre Giesecke , Frank Stefani , Johann Herault

We propose a one-channel, simple model to describe the dynamics of ultracold dipolar molecules around a F\"orster resonance. Slightly above a specific electric field, a collisional shielding can take place, suppressing the molecular losses…

Quantum Gases · Physics 2024-06-21 Lucas Lassablière , Goulven Quéméner

We present numerical magnetohydrodynamic (MHD) simulations of the effect of stellar dipole magnetic fields on line-driven wind outflows from hot, luminous stars. Unlike previous fixed-field analyses, the simulations here take full account…

Astrophysics · Physics 2011-05-05 Asif ud-Doula , Stanley P. Owocki

The growth of a large-scale magnetic field in the Sun and stars is usually possible when the dynamo number (D) is above a critical value Dc. As the star ages, its rotation rate and thus D decrease. Hence, the question is how far the solar…

Solar and Stellar Astrophysics · Physics 2025-01-07 Sanket Wavhal , Pawan Kumar , Bidya Binay Karak

We consider the three-dimensional instability of a layer of horizontal magnetic field in a polytropic atmosphere where, contrary to previous studies, the field lines in the initial state are not unidirectional. We show that if the twist is…

Solar and Stellar Astrophysics · Physics 2015-03-20 B. F. N. Favier , L. Jouve , W. Edmunds , L. J. Silvers , M. R. E. Proctor

We provide a numerical study of the macroscopic model of [3] derived from an agent-based model for a system of particles interacting through a dynamical network of links. Assuming that the network remodelling process is very fast, the…

In a previous paper we proposed a model to describe a gas of pyramidal molecules interacting via dipole-dipole interactions. The interaction modifies the tunneling properties between the classical equilibrium configurations of the single…

Statistical Mechanics · Physics 2007-05-23 Carlo Presilla , Giovanni Jona-Lasinio , Cristina Toninelli

This thesis presents a two-layer uniform facet elastic object for real-time simulation based on physics modeling method. It describes the elastic object procedural modeling algorithm with particle system from the simplest one-dimensional…

Graphics · Computer Science 2009-09-30 Miao Song

Solar magnetic activity shows both smooth secular changes, such as the Grand Modern Maximum, and quite abrupt drops that are denoted as Grand Minima. Direct numerical simulations (DNS) of convection driven dynamos offer one way of examining…

Solar and Stellar Astrophysics · Physics 2016-04-13 Maarit J. Käpylä , Petri J. Käpylä , Nigul Olspert , Axel Brandenburg , Jörn Warnecke , Bidya B. Karak , Jaan Pelt

It is known that diffusion provokes substantial changes in continuous absorbing phase transitions. Conversely, its effect on discontinuous transitions is much less understood. In order to shed light in this direction, we study the inclusion…

Statistical Mechanics · Physics 2014-09-25 Carlos E. Fiore , Gabriel T. Landi

Arguments are presented in favor of the idea that the solar dynamo may operate not just at the bottom of the convection zone, i.e. in the tachocline, but it may operate in a more distributed fashion in the entire convection zone. The…

Astrophysics · Physics 2007-05-23 Axel Brandenburg

We investigate numerically magnetic field generation by thermal convection with square periodicity cells in a rotating horizontal layer of electrically-conducting fluid with stress-free electrically perfectly conducting boundaries for…

Chaotic Dynamics · Physics 2010-04-12 V. Zheligovsky

Some selected concepts for the solar activity cycle are briefly reviewed. Cycle modulations through a stochastic alpha effect are being identified with limited scale separation ratios. Three-dimensional turbulence simulations with helicity…

Solar and Stellar Astrophysics · Physics 2012-07-17 Axel Brandenburg , Gustavo Guerrero

Twisted magnetic fields are frequently seen to emerge above the visible surface of the Sun. This emergence is usually associated with the rise of buoyant magnetic flux structures. Here we ask how magnetic fields from a turbulent large-scale…

Solar and Stellar Astrophysics · Physics 2010-11-22 J. Warnecke , A. Brandenburg

The geo and solar magnetic fields have long been thought to be very different objects both in terms of spatial structure and temporal behavior. The recently discovered field structure of a fully convective star is more reminiscent of…

Earth and Planetary Astrophysics · Physics 2009-07-30 Laure Goudard , Emmanuel Dormy

Computer simulations and scaling theory are used to investigate the damping of oscillations during epitaxial growth on high-symmetry surfaces. The crossover from smooth to rough growth takes place after the deposition of (D/F)^\delta…

Statistical Mechanics · Physics 2007-05-23 H. Kallabis , L. Brendel , P. Smilauer , J. Krug , D. E. Wolf

The climate is a complex non-equilibrium dynamical system that relaxes toward a steady state under the continuous input of solar radiation and dissipative mechanisms. The steady state is not necessarily unique. A useful tool to describe the…

Atmospheric and Oceanic Physics · Physics 2023-05-31 Maura Brunetti , Charline Ragon

Results of X-ray diffraction experiments on solid oxygen at low temperature and at pressures up to 10 GPa are presented.A careful sample preparation and annealing around 240 K allowed to obtain very good diffraction patterns in the…

Materials Science · Physics 2009-11-07 Federico A. Gorelli , Mario Santoro , Lorenzo Ulivi , Michael Hanfland

The meridional circulation plays an essential role in determining the basic mechanism of the dynamo action in case the of a low eddy diffusivity. Flux-transport dynamos with strong return flow and a deep stagnation point are discussed in…

Solar and Stellar Astrophysics · Physics 2015-06-03 Alfio Bonanno