Many-body forces in magnetic neutron stars

TL;DR

This paper investigates how many-body forces and magnetic fields influence the equation of state and structure of neutron stars, revealing their significant impact on star properties and particle populations.

Contribution

It introduces a relativistic mean field model incorporating many-body forces and analyzes magnetic field effects on neutron star structure and composition.

Findings

Magnetic fields and model parameterizations significantly affect star mass and shape.

Different magnetic field distributions alter internal density and magnetic profiles.

Strong magnetic fields substantially change particle populations within stars.

Abstract

In this work, we study in detail the effects of many-body forces on the equation of state and the structure of magnetic neutron stars. The stellar matter is described within a relativistic mean field formalism that takes into account many-body forces by means of a non-linear meson field dependence on the nuclear interaction coupling constants. We assume that matter is at zero temperature, charge neutral, in beta-equilibrium, and populated by the baryon octet, electrons, and muons. In order to study the effects of different degrees of stiffness in the equation of state, we explore the parameter space of the model, which reproduces nuclear matter properties at saturation, as well as massive neutron stars. Magnetic field effects are introduced both in the equation of state and in the macroscopic structure of stars by the self-consistent solution of the Einstein-Maxwell equations. In addition, effects of poloidal magnetic fields on the global properties of stars, as well as density and magnetic field profiles are investigated. We find that not only different macroscopic magnetic field distributions, but also different parameterizations of the model for a fixed magnetic field distribution impact the gravitational mass, deformation and internal density profiles of stars. Finally, we also show that strong magnetic fields affect significantly the particle populations of stars