Spinodal instabilities and the distillation effect in nuclear matter under strong magnetic fields

TL;DR

This paper investigates how intense magnetic fields influence the instability regions of nuclear matter, revealing effects like band formation, altered transition densities, and distillation phenomena relevant to neutron star crusts.

Contribution

It introduces a detailed analysis of magnetic field effects on nuclear matter instabilities using relativistic models, highlighting new instability behaviors and distillation effects.

Findings

Magnetic fields create bands of instability in nuclear matter.

Transition densities at neutron star crusts increase under strong magnetic fields.

Distillation effects are significantly affected by Landau level filling.

Abstract

We study the effect of strong magnetic fields, of the order of $10^{18}$-$10^{19}$ G, on the instability region of nuclear matter at subsaturation densities. Relativistic nuclear models both with constant couplings and with density dependent parameters are considered. It is shown that a strong magnetic field can have large effects on the instability regions giving rise to bands of instability and wider unstable regions. As a consequence we predict larger transition densities at the inner edge of the crust of compact stars with strong magnetic field. The direction of instability gives rise to a very strong distillation effect if the last Landau level is only partially filled. However, for almost completed Landau levels an anti-distillation effect may occur.