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Related papers: Magnetohydrodynamic equilibria in barotropic stars

200 papers

In this paper, the gravitational field equations for static spherically symmetric perfect fluid models with a polytropic equation of state, $p=k\rho^{1+1/n}$, are recast into two complementary 3-dimensional {\it regular} systems of ordinary…

General Relativity and Quantum Cosmology · Physics 2009-10-31 U. S. Nilsson , C. Uggla

We determine constraints on the form of axisymmetric toroidal magnetic fields dictated by hydrostatic balance in a type II superconducting neutron star with a barotropic equation of state. Using Lagrangian perturbation theory, we find the…

Astrophysics · Physics 2009-11-16 Taner Akgun , Ira Wasserman

We construct the first dynamically stable ergostars (equilibrium neutron stars that contain an ergoregion) for a compressible, causal equation of state. We demonstrate their stability by evolving both strict and perturbed equilibrium…

General Relativity and Quantum Cosmology · Physics 2019-12-11 Antonios Tsokaros , Milton Ruiz , Lunan Sun , Stuart L. Shapiro , Kōji Uryū

In this paper Einstein's field equations, for static spherically symmetric perfect fluid models with a linear barotropic equation of state, are recast into a 3-dimensional regular system of ordinary differential equations on a compact state…

General Relativity and Quantum Cosmology · Physics 2009-10-31 U. S. Nilsson , C. Uggla

Rotating relativistic stars have been studied extensively in recent years, both theoretically and observationally, because of the information they might yield about the equation of state of matter at extremely high densities and because…

High Energy Astrophysical Phenomena · Physics 2017-12-01 Vasileios Paschalidis , Nikolaos Stergioulas

Based on recent papers, we discuss the formulation of the first-order relativistic spin magnetohydrodynamics (MHD) with the totally antisymmetric spin current and properties of the anisotropic linear waves awaken near an equilibrium…

High Energy Physics - Phenomenology · Physics 2024-11-01 Zhe Fang , Koichi Hattori , Jin Hu

To find out whether toroidal field can stably exist in galaxies the current-driven instability of toroidal magnetic fields is considered under the influence of an axial magnetic field component and under the influence of both rigid and…

Astrophysics of Galaxies · Physics 2015-05-19 G. Ruediger , M. Schultz , D. Elstner

We reformulate in Lagrangian coordinates the two-phase free boundary problem for the equations of Magnetohydrodynamics in a infinite slab, which is incompressible, viscous and of zero resistivity, as one for the Navier-Stokes equations with…

Analysis of PDEs · Mathematics 2015-09-29 Yanjin Wang

This article introduces a new 3D magnetohydrodynamic (MHD) equilibrium solver, based on the concept of admissible variations of B, p that allows for magnetic relaxation of a magnetic field in a perturbed/non-minimum energy state to a lower…

Computational Physics · Physics 2025-11-03 Tobias Blickhan , Julianne Stratton , Alan A. Kaptanoglu

We consider the ideal magnetohydrodynamics (MHD) of a shallow fluid layer on a rapidly rotating planet or star. The presence of a background toroidal magnetic field is assumed, and the "shallow water" beta-plane approximation is used. We…

Earth and Planetary Astrophysics · Physics 2015-06-22 Alexander M. Balk

In certain astrophysical systems the commonly employed ideal magnetohydrodynamics (MHD) approximation breaks down. Here, we introduce novel explicit and implicit numerical schemes of ohmic resistivity terms in the moving-mesh code AREPO. We…

Instrumentation and Methods for Astrophysics · Physics 2018-03-09 Federico Marinacci , Mark Vogelsberger , Rahul Kannan , Philip Mocz , Rüdiger Pakmor , Volker Springel

The stability of large-scale magnetic fields in rotating stars is explored, using 3D numerical hydrodynamics to follow the evolution of an initial poloidal field. It is found that the field is subject to an instability, located initially on…

Astrophysics · Physics 2009-11-13 J. Braithwaite

Context. Prominence seismology exploits our knowledge of the linear eigenoscillations for representative magnetohydro- dynamic models of filaments. To date, highly idealized models for prominences have been used, especially with respect to…

Solar and Stellar Astrophysics · Physics 2011-06-27 J. W. S. Blokland , R. Keppens

A new code for computing fully general relativistic solutions of strongly magnetized rapidly rotating compact stars is developed as a part of the COCAL (Compact Object CALculator) code. The full set of Einstein's equations, Maxwell's…

General Relativity and Quantum Cosmology · Physics 2019-12-25 Koji Uryu , Shijun Yoshida , Eric Gourgoulhon , Charalampos Markakis , Kotaro Fujisawa , Antonios Tsokaros , Keisuke Taniguchi , Yoshiharu Eriguchi

In this work, we generalise linear magnetohydrodynamic (MHD) stability theory to include equilibrium pressure anisotropy in the fluid part of the analysis. A novel 'single-adiabatic' (SA) fluid closure is presented which is complementary to…

Plasma Physics · Physics 2015-10-29 M. Fitzgerald , M. J. Hole , Z. S. Qu

We study gravito-magnetic instabilities of a static homogeneous medium with an aligned magnetic field in the two contexts of relativistic magnetohydrodynamics (MHD): first, MHD with post-Newtonian (PN) corrections, and second, special…

High Energy Astrophysical Phenomena · Physics 2021-01-13 Hyerim Noh , Jai-chan Hwang

We study the Rayleigh-Taylor problem for two incompressible, immiscible, viscous magnetohydrodynamic (MHD) flows, with zero resistivity, surface tension (or without surface tenstion) and special initial magnetic field, evolving with a free…

General Mathematics · Mathematics 2012-05-02 Fei Jiang , Song Jiang , Yanjin Wang

The stability of matter composed of electrons and static nuclei is investigated for a relativistic dynamics for the electrons given by a suitably projected Dirac operator and with Coulomb interactions. In addition there is an arbitrary…

Statistical Mechanics · Physics 2009-10-28 Elliott H. Lieb , Heinz Siedentop , Jan Philip Solovej

We calculate non-axisymmetric oscillations of neutron stars magnetized by purely poloidal magnetic fields. We use polytropes of index $n=1$ and 1.5 as a background model, where we ignore the equilibrium deformation due to the magnetic…

High Energy Astrophysical Phenomena · Physics 2015-12-16 Hidetaka Asai , Umin Lee , Shijun Yoshida

Motivated by the current search for exomoons, this paper considers the stability of tidal equilibrium for hierarchical three-body systems containing a star, a planet, and a moon. In this treatment, the energy and angular momentum budgets…

Earth and Planetary Astrophysics · Physics 2016-08-31 Fred C. Adams , Anthony M. Bloch