Skyrme model study of proton and neutron properties in a strong magnetic field

TL;DR

This study uses the Skyrme model to analyze how strong magnetic fields affect proton and neutron properties, revealing mass, size, and magnetic moment changes that influence magnetar core physics.

Contribution

It provides a novel analysis of baryon property modifications under intense magnetic fields using the Skyrme model, linking microscopic changes to magnetar equations of state.

Findings

Proton mass decreases then increases with magnetic field strength.

Neutron mass always increases as magnetic field strength grows.

Proton size first increases then decreases under strong magnetic fields.

Abstract

The proton and neutron properties in a uniform magnetic field are investigated. The Gell-Mann-Nishijima formula is shown to be satisfied for baryon states. It is found that with increasing magnetic field strength, the proton mass first decreases and then increases, while the neutron mass always increases. The ratio between magnetic moment of proton and neutron increases with the increase of the magnetic field strength. With increasing magnetic field strength, the size of proton first increases and then decreases, while the size of neutron always decreases. The present analyse implies that in the core part of the magnetar, the equation of state depend on the magnetic field, which modifies the mass limit of the magnetar.