Ferromagnetic condensation in high density hadronic matter

TL;DR

This paper explores the possibility of ferromagnetic phase transitions in high-density hadronic matter, such as in neutron stars, predicting significant magnetization and phase changes at extreme densities.

Contribution

It introduces a model for ferromagnetic transitions in quark matter using a four-fermion interaction analogous to chiral symmetry breaking, analyzing different flavor phases.

Findings

Second order phase transition at about 5 times nuclear density

Magnetization of approximately 10^16 gauss predicted

First order transition from 2SC to ferromagnetic phase in SU(3) quark matter

Abstract

We investigate the occurrence of a ferromagnetic phase transition in high density hadronic matter (e.g., in the interior of a neutron star). This could be induced by a four fermion interaction analogous to the one which is responsible for chiral symmetry breaking in the Nambu-Jona-Lasinio model, to which it is related through a Fierz transformation. Flavor SU(2) and flavor SU(3) quark matter are considered. A second order phase transition is predicted at densities about 5 times the normal nuclear matter density, a magnetization of the order of $10^{16}$ gauss being expected. It is also found that in flavor SU(3) quark matter, a first order transition from the so-called 2 flavor super-conducting (2SC) phase to the ferromagnetic phase arises. The color-flavor-locked (CFL) phase may be completely hidden by the ferromagnetic phase.