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Related papers: Stable Magnetic Fields in Static Stars

200 papers

Concerning the stability of two-fluid star models, we prove the rigorous equivalence of two independent determining methods for mixed stars, after a brief review of the hybrid star case. Our derivations apply to general multi-fluid cases,…

High Energy Astrophysical Phenomena · Physics 2025-12-02 Xiao-Ding Zhou , Tian-Shun Chen , Si-Man Wu , Kilar Zhang

Although indirect evidence for the presence of magnetic fields in high-mass stars is regularly reported in the literature, the detection of these fields remains an extremely challenging observational problem. We review the recent…

Astrophysics · Physics 2007-05-23 S. Hubrig

Although barotropic matter does not constitute a realistic model for magnetic stars, it would be interesting to confirm a recent conjecture that states that magnetized stars with a barotropic equation of state would be dynamically unstable…

Solar and Stellar Astrophysics · Physics 2015-06-15 Cristobal Armaza , Andreas Reisenegger , Juan Alejandro Valdivia , Pablo Marchant

Stably stratified fluid layers are common in gaseous planets, stellar interiors, and planetary cores, and have long been considered incapable of sustaining dynamo action. Here, we show that semiconvection - driven by a destabilizing thermal…

Earth and Planetary Astrophysics · Physics 2025-11-26 Paul Pružina , David Cébron , Nathanaël Schaeffer

Stably stratified layers are present in stellar interiors (radiative zones) as well as planetary interiors - recent observations and theoretical studies of the Earth's magnetic field seem to indicate the presence of a thin, stably…

Solar and Stellar Astrophysics · Physics 2019-10-10 J. Philidet , C. Gissinger , F. Lignières , L. Petitdemange

Are the kG-strength magnetic fields observed in young stars a fossil field left over from their formation or are they generated by a dynamo? We use radiation non-ideal magnetohydrodynamics simulations of the gravitational collapse of a…

Solar and Stellar Astrophysics · Physics 2018-09-12 James Wurster , Matthew R. Bate , Daniel J. Price

It is now believed that magnetohydrodynamic equilibria can exist in stably stratified stars due to the seminal works of Braithwaite & Spruit (2004) and Braithwaite & Nordlund (2006). What is still not known is whether magnetohydrodynamic…

Solar and Stellar Astrophysics · Physics 2015-06-17 J. P. Mitchell , J. Braithwaite , N. Langer , A. Reisenegger , H. Spruit

We conduct 3D magneto-hydrodynamic (MHD) simulations in order to test the stability of the magnetic equilibrium configuration described by Duez & Mathis (2010). This analytically-derived configuration describes the lowest energy state for a…

Solar and Stellar Astrophysics · Physics 2015-05-20 V. Duez , J. Braithwaite , S. Mathis

An arbitrary initial magnetic field in an A star evolves into a stable equilibrium. Simulations are presented of the formation of non-axisymmetric equilibria consisting of twisted flux tubes meandering under the surface of the star, and…

Astrophysics · Physics 2008-01-31 Jonathan Braithwaite

As an alternative gravity model we consider an extended Einstein-Maxwell gravity containing a gauge invariance property. Extension is assumed to be addition of a directional coupling between spatial electromagnetic fields with the Ricci…

General Relativity and Quantum Cosmology · Physics 2024-01-08 Hossein Ghaffarnejad , Leyla Naderi

We perform a thorough analysis of the dynamic and thermodynamic stability for the charged perfect fluid star by applying the Wald formalism to the Lagrangian formulation of Einstein-Maxwell-charged fluid system. As a result, we find that…

General Relativity and Quantum Cosmology · Physics 2023-06-21 Kai Shi , Yu Tian , Xiaoning Wu , Hongbao Zhang , Jingchao Zhang

We investigate the chiral magnetic instability in the crust of a neutron star as a potential mechanism for amplifying magnetic fields. This instability may become active when small deviations from chemical equilibrium are sustained over…

High Energy Astrophysical Phenomena · Physics 2024-08-13 Clara Dehman , José A. Pons

Ap star magnetism is often attributed to fossil magnetic fields which have not changed much since the pre-main-sequence epoch of the stars. Stable magnetic field configurations are known which could persist probably for the entire…

Solar and Stellar Astrophysics · Physics 2015-05-20 R. Arlt , G. Ruediger

Physical experiments and numerical simulations have observed a remarkable stabilizing phenomenon: a background magnetic field stabilizes and damps electrically conducting fluids. This paper intends to establish this phenomenon as a…

Analysis of PDEs · Mathematics 2022-11-01 Hongxia Lin , Jiahong Wu , Yi Zhu

Current-carrying flows, in the laboratory and in astrophysical jets, can form remarkably stable magnetic structures. Decades of experience shows that such flows often build equilibria that reverse field directions, evolving to an MHD Taylor…

Astrophysics · Physics 2009-11-11 Gregory Benford

We examine the existence of relativistic stars in f(T) modified gravity and explicitly construct several classes of static perfect fluid solutions. We derive the conservation equation from the complete f(T) gravity field equations and…

General Relativity and Quantum Cosmology · Physics 2012-11-13 Christian G. Boehmer , Atifah Mussa , Nicola Tamanini

Stellar magnetism plays an important role in stellar evolution theory. Approximatively 10% of observed main sequence (MS) and pre-main-sequence (PMS) radiative stars exhibit surface magnetic fields above the detection limit, raising the…

Solar and Stellar Astrophysics · Physics 2018-01-24 Jérémie Vidal , David Cébron , Nathanaël Schaeffer , Rainer Hollerbach

This paper presents a global stability result on perturbations near a background magnetic field to the 2D incompressible magnetohydrodynamic (MHD) equations with only magnetic diffusion on the periodic domain. The stability result provides…

Analysis of PDEs · Mathematics 2024-02-16 Xiaoping Zhai

Convection in massive main sequence stars generates large scale magnetic fields in their cores which persists as they evolve up the red giant branch. The remnants of these fields may take the form of the Prendergast magnetic field, a…

Solar and Stellar Astrophysics · Physics 2022-10-12 Emma Kaufman , Daniel Lecoanet , Evan H. Anders , Benjamin P. Brown , Geoffrey M. Vasil , Jeffrey S. Oishi , Keaton J. Burns

A variety of magnetohydrodynamic mechanisms that may play a role in magnetic, chemically peculiar (mCP) stars is reviewed. These involve dynamo mechanisms in laminar flows as well as turbulent environments, and magnetic instabilities of…

Astrophysics · Physics 2008-01-30 R. Arlt