The role of currents distribution in general relativistic equilibria of magnetized neutron stars

TL;DR

This paper investigates how different current distributions affect the magnetic field structure and overall equilibrium of magnetized neutron stars within a general relativistic framework, revealing dominant poloidal components across various configurations.

Contribution

It provides the first detailed parameter study of current distribution effects on neutron star magnetic fields in general relativity, highlighting the impact on surface field strength and structure.

Findings

Localized currents can significantly alter surface magnetic field strength.

Magnetic configurations are generally dominated by poloidal currents.

The study offers insights into the energetic and structural trends of neutron star magnetic fields.

Abstract

Magnetic fields play a critical role in the phenomenology of neutron stars. There is virtually no observable aspect which is not governed by them. Despite this, only recently efforts have been done to model magnetic fields in the correct general relativistic regime, characteristic of these compact objects. In this work we present, for the first time a comprehensive and detailed parameter study, in general relativity, of the role that the current distribution, and the related magnetic field structure, have in determining the precise structure of neutron stars. In particular, we show how the presence of localized currents can modify the field strength at the stellar surface, and we look for general trends, both in terms of energetic properties, and magnetic field configurations. Here we verify that, among other things, for a large class of different current distributions the resulting magnetic configurations are always dominated by the poloidal component of the current.