Magnetic properties of strongly asymmetric nuclear matter in a Dirac-Hartree-Fock approach

The magnetic susceptibility of strongly asymmetric nuclear matter, at relevant densities in neutron stars, is studied in the framework of a relativistic σ + ω + π + ϱ Hartree-Fock approach. The presence of protons, through their interaction with neutrons, means that formation of spontaneous magnetized matter occurs at lower densities than in pure neutron matter. A possible ferromagnetic transition is predicted at about four times the nuclear matter saturation density.