English
Related papers

Related papers: Structure of magnetic fields in non-convective sta…

200 papers

Recent spectro-polarimetric observations of solar-type stars have shown the presence of photospheric magnetic fields with a predominant toroidal component. If the external field is assumed to be current-free it is impossible to explain…

Solar and Stellar Astrophysics · Physics 2016-12-21 Alfio Bonanno

Equilibrium configurations of the internal magnetic field of a pulsar play a key role in modeling astrophysical phenomena, from glitches to gravitational wave emission. In this paper we present a numerical scheme for solving the…

High Energy Astrophysical Phenomena · Physics 2022-08-09 Ankan Sur , Brynmor Haskell

We study the stability of neutron stars with toroidal magnetic fields by magnetohydrodynamic simulation in full general relativity under assumption of axial symmetry. Nonrotating and rigidly rotating neutron stars are prepared for a variety…

Astrophysics · Physics 2008-12-18 Kenta Kiuchi , Masaru Shibata , Shijun Yoshida

We derive axisymmetric equilibrium equations in the context of the hybrid Vlasov model with kinetic ions and massless fluid electrons, assuming isothermal electrons and deformed Maxwellian distribution functions for the kinetic ions. The…

Plasma Physics · Physics 2024-06-06 D. A. Kaltsas , A. Kuiroukidis , P. J. Morrison , G. N. Throumoulopoulos

Using an axisymmetric numerical code, we perform an extensive study of the magnetic field configurations in non-rotating neutron stars, varying the mass, magnetic field strength and the equation of state. We find that the monopolar…

Nuclear Theory · Physics 2019-06-12 Debarati Chatterjee , Jerome Novak , Micaela Oertel

We study the time evolution of non-axisymmetric linear perturbations of a rotating magnetised neutron star, whose magnetic field is multipolar and purely poloidal. The background stellar configurations are generated self-consistently,…

Solar and Stellar Astrophysics · Physics 2015-05-20 S. K. Lander , D. I. Jones

We obtain the general forms for the current density and the vorticity from the integrability conditions of the basic equations which govern the stationary states of axisymmetric magnetized self-gravitating barotropic objects with meridional…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Kotaro Fujisawa , Rohta Takahashi , Shijun Yoshida , Yoshiharu Eriguchi

Symmetries and conservation laws associated with the ideal Einstein-Euler system, for stationary and axisymmetric stars, can be utilized to define a set of flow constants. These quantities are conserved along flow lines in the sense that…

General Relativity and Quantum Cosmology · Physics 2023-10-05 Arthur G. Suvorov , Kostas Glampedakis

Magnetic fields represent a crucial aspect of the physics and astrophysics of neutron stars. Despite its great relevance, the internal magnetic field configuration of neutron stars is very poorly constrained by the observations, and…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Riccardo Ciolfi

Context. Stellar magnetic fields are one of the candidates often invoked to explain the missing transport of angular momentum observed in the models of stellar interiors. However, the properties of an internal magnetic field and the…

Solar and Stellar Astrophysics · Physics 2019-07-03 V. Prat , S. Mathis , B. Buysschaert , J. Van Beeck , D. M. Bowman , C. Aerts , C. Neiner

Observations of magnetic A, B and O stars show that the poloidal magnetic flux per unit mass has an upper bound of 10^-6.5 G cm^2/g. A similar upper bound is found for magnetic white dwarfs even though the highest magnetic field strengths…

Solar and Stellar Astrophysics · Physics 2015-06-17 Dayal T. Wickramasinghe , Christopher A. Tout , Lilia Ferrario

We calculate non-axisymmetric oscillations of uniformly rotating polytropes magnetized with a purely toroidal magnetic field, taking account of the effects of the deformation due to the magnetic field. As for rotation, we consider only the…

Solar and Stellar Astrophysics · Physics 2015-06-24 Hidetaka Asai , Umin Lee , Shijun Yoshida

We explore magnetic field configurations that lead to the formation of magnetic spots on the surface of neutron stars, and to the displacement of the magnetic dipole axis. We find that a toroidally dominated magnetic field is essential for…

High Energy Astrophysical Phenomena · Physics 2018-01-08 Konstantinos N. Gourgouliatos , Rainer Hollerbach

By choosing appropriate deformed Maxwellian ion and electron distribution functions depending on the two particle constants of motion, i.e. the energy and toroidal angular momentum, we reduce the Vlasov axisymmetric equilibrium problem for…

Plasma Physics · Physics 2015-08-12 Ap Kuiroukidis , G. N. Throumoulopoulos , H. Tasso

Magnetars have inferred polar field strengths in excess of the Schwinger limit, where non-linear electromagnetic effects can be significant. Their internal fields may be even stronger, suggesting that Maxwellian characterizations of…

High Energy Astrophysical Phenomena · Physics 2025-05-12 Arthur G. Suvorov , José A. Pons

We construct magnetized stars composed of a fluid stably stratified by entropy gradients in the framework of general relativity, assuming ideal magnetohydrodynamics and employing a barotropic equation of state. We first revisit basic…

General Relativity and Quantum Cosmology · Physics 2015-06-05 Shijun Yoshida , Kenta Kiuchi , Masaru Shibata

Strong magnetic fields play an important role in powering the emission of neutron stars. Nevertheless a full understanding of the interior configuration of the field remains elusive. In this work, we present General Relativistic…

High Energy Astrophysical Phenomena · Physics 2022-02-16 Ankan Sur , William Cook , David Radice , Brynmor Haskell , Sebastiano Bernuzzi

In the framework of Einstein-Maxwell-axion theory we consider a static field configuration in the outer zone of a magnetic star. We assume that this field configuration is formed by the following interacting quartet: a spherically symmetric…

General Relativity and Quantum Cosmology · Physics 2020-01-27 Alexander B. Balakin , Dmitry E. Groshev

Stability properties of magnetic-field configurations containing the toroidal and axial field are considered. The stability is treated by making use of linear analysis. It is shown that the conditions required for the onset of instability…

Astrophysics · Physics 2009-11-13 Alfio Bonanno , Vadim Urpin

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