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Ion anisotropies can affect a host of processes within the magnetosphere, from modifying the growth rate of various instabilities to the energization and mass transport within the magnetosphere. Global multi-fluid simulations using a full…

Earth and Planetary Astrophysics · Physics 2016-05-05 Robert Winglee , Erika Harnett

This report describes a new magnetohydrodynamic numerical model based on a hexagonal spherical geodesic grid. The model is designed to simulate astrophysical flows of partially ionized plasmas around a central compact object, such as a star…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 V. Florinski , X. Guo , D. S. Balsara , C. Meyer

Analytical solution has been found for the second-order effective anisotropy of magnetic nanoparticles of a cubic shape due to the surface anisotropy (SA) of the N\'eel type. Similarly to the spherical particles, for the simple cubic…

Mesoscale and Nanoscale Physics · Physics 2018-09-12 D. A. Garanin

We consider the numerical solution of time-dependent space tempered fractional diffusion equations. The use of Crank-Nicolson in time and of second-order accurate tempered weighted and shifted Gr\"unwald difference in space leads to dense…

Numerical Analysis · Mathematics 2022-10-12 D. Ahmad , M. Donatelli , M. Mazza , S. Serra-Capizzano , K. Trotti

The formation of macroscopic reconnected magnetic structures (islands) have been observed in advanced experiments on weakly collisional, well confined plasmas while established theories of the drift-tearing modes, which depend strongly on…

Plasma Physics · Physics 2017-08-23 B. Coppi

Thermodynamic perturbation theory is employed to derive analytical expressions for the equilibrium linear susceptibility and specific heat of lattices of anisotropic classical spins weakly coupled by the dipole-dipole interaction. The…

Materials Science · Physics 2009-11-07 P. E. Jönsson , J. L. Garcia-Palacios

The polytropic index of electrons in a magnetized plasma is experimentally investigated in the presence of heating and anisotropic work done, incorporating the effective dimensionality arising from temperature anisotropy. The study is…

Plasma Physics · Physics 2024-10-18 Ayesha Nanda , Sudeep Bhattacharjee

We extend the recently proposed semi-Lagrangian algorithm for the extremely anisotropic heat transport equation [Chac\'on et al., J. Comput. Phys., 272 (2014)] to deal with arbitrary magnetic field topologies. The original scheme (which…

Numerical Analysis · Mathematics 2024-08-07 L. Chacon , G. Di Giannatale

The validity of two approximative linear tensor models to be used for grating based X-ray or neutron dark-field tensor tomography is investigated in a simulation study. While the dark-field contrast originating from anisotropic microscopic…

Medical Physics · Physics 2021-09-24 Jonas Graetz

It is believed that plasma rotation can affect the transitions to the advanced confinement regimes in tokamaks. In addition, in order to achieve fusion temperatures modern tokamaks rely on auxiliary heating methods. These methods generate…

Plasma Physics · Physics 2020-09-23 G. Poulipoulis , G. N. Throumoulopoulos

In this work we extend the shifted Laplacian approach to the elastic Helmholtz equation. The shifted Laplacian multigrid method is a common preconditioning approach for the discretized acoustic Helmholtz equation. In some cases, like…

Computational Engineering, Finance, and Science · Computer Science 2023-11-21 Eran Treister , Rachel Yovel

We investigate the thermodynamics of the anisotropic magnetic $\rm AdS_5$ black brane solution found by D'Hoker and Kraus arXiv:0908.3875. This solution is the gravity dual of a strongly coupled ${\cal N}=4$ Super Yang-Mills plasma in…

High Energy Physics - Theory · Physics 2022-07-13 Alfonso Ballon-Bayona , Jonathan P. Shock , Dimitrios Zoakos

We present a general approach to the derivation of the effective anisotropy field which determines the dynamical behaviour of magnetic spins according to the Landau-Lifshitz-Gilbert equation. The approach is based on the gradient in…

The most general form of the nonrelativistic Grad-Shafranov equation describing anisotropic pressure effects is formulated within the double adiabatic approximation. It gives a possibility to analyze quantitatively how the anisotropic…

Astrophysics · Physics 2009-10-31 V. S. Beskin , I. V. Kuznetsova

This paper develops efficient preconditioned iterative solvers for incompressible flow problems discretised by an enriched Taylor-Hood mixed approximation, in which the usual pressure space is augmented by a piecewise constant pressure to…

Numerical Analysis · Mathematics 2024-05-29 Jennifer Pestana , David J. Silvester

The translational dynamics in a repulsive colloidal glass-former is probed by time-resolved X-ray Photon Correlation Spectroscopy. In this dense dispersion of charge-stabilized and magnetic nanoparticles, the interaction potential can be…

Soft Condensed Matter · Physics 2015-02-04 E Wandersman , Y Chushkin , E Dubois , V Dupuis , A Robert , R Perzynski

This work presents a multigrid preconditioned high order immersed finite difference solver to accurately and efficiently solve the Poisson equation on complex 2D and 3D domains. The solver employs a low order Shortley-Weller multigrid…

Numerical Analysis · Mathematics 2025-03-31 James Gabbard , Andrea Paris , Wim M. van Rees

This paper presents a large-scale parallel solver, specifically designed to tackle the challenges of solving high-dimensional and high-contrast linear systems in heat transfer topology optimization. The solver incorporates an interpolation…

Numerical Analysis · Mathematics 2025-01-14 Yingjie Zhou , Changqing Ye , Yucheng Liu , Shubin Fu , Eric T. Chung

The Foldy-Lax (or the point-interaction) approximation of the electromagnetic fields generated by a cluster of small scaled inhomogeneities is derived in the mesoscale regime, i.e. when the minimum distance $\delta$ between the particles is…

Analysis of PDEs · Mathematics 2019-11-21 Ali Bouzekri , Mourad Sini

An inhomogeneous cosmological magnetic field creates vortical perturbations that survive Silk damping on much smaller scales than compressional modes. This ensures that there is no sharp cut-off in anisotropy on arc-minute scales. As we had…

Astrophysics · Physics 2009-11-07 Kandaswamy Subramanian , John D. Barrow
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