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Related papers: Reconstructing Highly-twisted Magnetic Fields

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Magnetars exhibit a variety of transient high-energy phenomena in the form of bursts, outbursts, and giant flares. It is a common belief that these events originate in the sudden release of magnetic energy due to the rearrangement of a…

High Energy Astrophysical Phenomena · Physics 2023-03-22 Petros Stefanou , Jose A. Pons , Pablo Cerdá-Durán

AIMS: We develop an optimization principle for computing stationary MHD equilibria. METHODS: Our code for the self-consistent computation of the coronal magnetic fields and the coronal plasma uses non-force-free MHD equilibria. Previous…

Astrophysics · Physics 2008-11-26 Thomas Wiegelmann , Thomas Neukirch

An efficient numerical code FP3D has been developed to calculate particle orbits and evaluate particle confinement in 3D magnetic fields including stellarators and tokamaks with 3D fields. The magnetic field is either calculated from coils…

Plasma Physics · Physics 2023-10-13 P. Y. Jiang , Z. C. Feng , G. D. Yu , G. Y. Fu

A hybrid spectral/finite-element code is developed to numerically solve the resistive finite-pressure magnetohydrodynamic equilibria without the necessity of postulating nested magnetic flux surfaces in the non-axisymmetric toroidal…

Plasma Physics · Physics 2024-12-30 Jian Zhang , Ping Zhu , Chris C. Hegna

With the development of new instrumentation providing measurements of solar photospheric vector magnetic fields, we need to develop our understanding of the effects of current density on coronal magnetic field configurations. The object is…

Astrophysics · Physics 2009-11-13 S. Regnier , E. R. Priest

We consider the force-free magnetosphere of an aligned rotator. Its structure is well described by a Grad-Shafranov equation for poloidal magnetic field, the so-called "pulsar equation". We solve this equation by a multigrid method with…

Astrophysics · Physics 2009-11-13 Andrey Timokhin

Slender magnetic elements provide a versatile platform for programmable shape-morphing under remote magnetic actuation. However, a general and physically interpretable framework for the inverse design of a `magneto-elastica' under…

Soft Condensed Matter · Physics 2026-04-15 JiaHao Li , Yingchao Zhang , Weicheng Huang , Shenghao Ye , HengAn Wu , Dominic Vella , Mingchao Liu

In this work we describe a numerical optimization method for computing stationary MHD-equilibria. The newly developed code is based on a nonlinear force-free optimization principle. We apply our code to model the solar corona using synoptic…

Solar and Stellar Astrophysics · Physics 2020-11-11 Thomas Wiegelmann , Thomas Neukirch , Dieter H. Nickeler , Iulia Chifu

The X-ray spectra observed in the persistent emission of magnetars are evidence for the existence of a magnetosphere. The high-energy part of the spectra is explained by resonant cyclotron upscattering of soft thermal photons in a twisted…

High Energy Astrophysical Phenomena · Physics 2011-09-28 Daniele Viganò , Jose A. Pons , Juan A. Miralles

The properties of magnons hosted in strained Heisenberg-Kitaev magnets are investigated using numerical and analytical calculations. Considering that deformation fields modulate the coupling parameters, we find a general expression for the…

Mesoscale and Nanoscale Physics · Physics 2025-04-30 Miguel Letelier , Roberto E. Troncoso , Nicolas Vidal-Silva

A 3-D coronal magnetic field is reconstructed for NOAA 11158 on Feb 14, 2011. A GPU-accelerated direct boundary integral equation (DBIE) method is implemented. This is about 1000 times faster than the original DBIE used on solar NLFFF…

Solar and Stellar Astrophysics · Physics 2015-06-16 Rui Wang , Yihua Yan , Baolin Tan

Accurate reconstruction of magnetic fields in inaccessible regions is vital for many high-precision experiments in physics. Traditional methods, such as spherical harmonic expansion, often suffer from truncation errors that limit their…

Instrumentation and Detectors · Physics 2026-05-26 Haohan Yu , Zhanxu Hao , Bingzhi Li , Zejia Lu , Xiang Chen , Liang Li

In micromagnetic simulations, the demagnetization field is by far the computationally most expensive field component and often a limiting factor in large multilayer systems. We present an exact method to calculate the demagnetization field…

Computational Physics · Physics 2020-03-18 Paul Heistracher , Florian Bruckner , Claas Abert , Christoph Vogler , Dieter Suess

We find general relativistic solutions of equilibrium magnetic field configurations in magnetars, extending previous results of Colaiuda et al. (2008). Our method is based on the solution of the relativistic Grad-Shafranov equation, to…

Solar and Stellar Astrophysics · Physics 2010-11-02 R. Ciolfi , V. Ferrari , L. Gualtieri , J. A. Pons

Well controlled and highly stable magnetic fields are desired for a wide range of applications in physical research, including quantum metrology, sensing, information processing, and simulation. Here we introduce a low-cost hybrid assembly…

Quantum Physics · Physics 2018-12-21 Frederick Hakelberg , Philip Kiefer , Matthias Wittemer , Tobias Schaetz , Ulrich Warring

Single Helical Axis (SHAx) configurations are emerging as the natural state for high current reversed field pinch (RFP) plasmas. These states feature the presence of transport barriers in the core plasma. Here we present a method for…

The FLARE code is a magnetic mesh generator that is integrated within a suite of tools for the analysis of the magnetic geometry in toroidal fusion devices. A magnetic mesh is constructed from field line segments and permits fast…

Plasma Physics · Physics 2024-09-11 H. Frerichs

We investigate in details properties of stationary force-free magnetosphere of aligned rotator assuming the last closed field line lying in equatorial plane at large distances from pulsar. The pulsar equations is solved numerically using…

Astrophysics · Physics 2009-11-11 A. N. Timokhin

We present a code for solving the nonlinear force-free equations in spherical polar geometry, with the motivation of modeling the magnetic field in the corona. The code is an implementation of the Grad-Rubin method. Our method is applicable…

Solar and Stellar Astrophysics · Physics 2016-10-28 S. A. Gilchrist , M. S. Wheatland

The accurate construction of tokamak equilibria, which is critical for the effective control and optimization of plasma configurations, depends on the precise distribution of magnetic fields and magnetic fluxes. Equilibrium fitting codes,…