Related papers: Non-dipolar magnetic fields in Ap stars
In previous work stable approximately axisymmetric equilibrium configurations for magnetic stars were found by numerical simulation. Here I investigate the conditions under which more complex, non-axisymmetric configurations can form. I…
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…
Neutron stars contain persistent, ordered magnetic fields that are the strongest known in the Universe. However, their magnetic fluxes are similar to those in magnetic A and B stars and white dwarfs, suggesting that flux conservation during…
Large-scale magnetic fields of Ap/Bp stars are stable over long timescales and have typically simple dipolar geometries, leading to the idea of a fossil origin. These stars are also expected to have convective cores that can host strong…
The existence of stable magnetic configurations in white dwarfs, neutron stars and various non-convective stellar {regions} is now well recognized. It has recently been shown numerically that various families of equilibria, including…
The magnetic fields observed in Ap-stars, white dwarfs, and neutron stars are known to be stable for long times. However, the physical conditions inside the stellar interiors that allow these states are still a matter of research. It has…
While the presence of magnetic fields on low-mass stars is attributed to a dynamo process essentially driven by convective motions, the existence of magnetic fields on intermediate-mass stars has very likely other reasons. Presuming that…
This study is concerned with the early evolution of magnetic fields and differential rotation of intermediate-mass stars which may evolve into Ap stars. We report on simulations of the interplay of differential rotation and magnetic fields,…
As another step towards understanding the long-term evolution of the magnetic field in neutron stars, we provide the first simulations of ambipolar diffusion in a spherical star. Restricting ourselves to axial symmetry, we consider a…
We review the current state of knowledge of magnetic fields inside stars, concentrating on recent developments concerning magnetic fields in stably stratified (zones of) stars, leaving out convective dynamo theories and observations of…
We investigate the 50-year old hypothesis that the magnetic fields of the Ap stars are stable equilibria that have survived in these stars since their formation. With numerical simulations we find that stable magnetic field configurations…
The problem of the stability of magnetic fields in stars has a long history and has been investigated in detail in perturbation theory. Here we consider the nonlinear evolution of a non-rotating neutron star with a purely poloidal magnetic…
Magnetic fields in upper main-sequence stars, white dwarfs, and neutron stars are known to persist for timescales comparable to their lifetimes. From a theoretical perspective this is problematic, as it can be shown that simple magnetic…
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…
The aim of this paper is to clarify the stabilities of neutron stars with strong toroidal magnetic fields against non-axisymmetric perturbation. The motivation comes from the fact that super magnetized neutron stars of $\sim 10^{15}$G,…
Magnetic perturbations to the frequencies of low degree, high radial order, axisymmetric pulsations in stellar models permeated by large scale magnetic fields are presented. Magnetic fields with dipolar, quadrupolar and a superposition of…
Using a numerical simulation, we study the effects of ambipolar diffusion and ohmic diffusion on the magnetic field evolution in the interior of an isolated neutron star. We are interested in the behavior of the magnetic field on a long…
Peculiar A stars are so named because they exhibit abundance peculiarities in their atmospheres. It is believed that these arise as a result of differentiation of chemical species in large magnetic spots in which convective mixing is…
Some main-sequence stars of spectral type A are observed to have a strong (300-30000 G), static, large-scale magnetic field, of a chiefly dipolar shape -- the `Ap stars' (for example Alioth, the fifth star in the Big Dipper). Following…
Stars are, generically, rotating and magnetised objects with a misalignment between their magnetic and rotation axes. Since a magnetic field induces a permanent distortion to its host, it provides effective rigidity even to a fluid star,…