General-relativistic resistive-magnetohydrodynamics simulations of self-consistent magnetized rotating neutron stars

TL;DR

This paper presents the first general-relativistic resistive magnetohydrodynamics simulations of rotating neutron stars, revealing resistivity's significant impact on magnetic field evolution and gravitational wave emission.

Contribution

It introduces a novel simulation approach for neutron stars incorporating resistivity, showing its effects on magnetic instabilities and field configurations.

Findings

Resistivity influences the development of MHD instabilities.

Resistivity suppresses instability growth and reduces gravitational wave amplitudes.

The poloidal to toroidal magnetic energy ratio remains at 9:1 across models.

Abstract

We present the first general-relativistic resistive magnetohydrodynamics simulations of self-consistent, rotating neutron stars with mixed poloidal and toroidal magnetic fields. Specifically, we investigate the role of resistivity in the dynamical evolution of neutron stars over a period of up to 100 ms and its effects on their quasi-equilibrium configurations. Our results demonstrate that resistivity can significantly influence the development of magnetohydrodynamic instabilities, resulting in markedly different magnetic field geometries. Additionally, resistivity suppresses the growth of these instabilities, leading to a reduction in the amplitude of emitted gravitational waves. Despite the variations in magnetic field geometries, the ratio of poloidal to toroidal field energies remains consistently 9:1 throughout the simulations, for the models we investigated.