Neutron star crust beyond the Wigner-Seitz approximation

TL;DR

This paper explores the limitations of the Wigner-Seitz approximation in modeling neutron star crusts and introduces a band theory approach revealing that unbound neutrons behave as if their mass is increased.

Contribution

It applies band theory to neutron star crusts, providing a more accurate description of unbound neutron behavior beyond traditional approximations.

Findings

Unbound neutrons exhibit effective mass increase in the crust.

Band theory offers a new framework for neutron star crust modeling.

Wigner-Seitz approximation validity is critically assessed.

Abstract

For more than three decades, the inner crust of neutron stars, formed of a solid lattice of nuclear clusters coexisting with a gas of electrons and neutrons, has been traditionally studied in the Wigner-Seitz approximation. The validity of this approximation is discussed in the general framework of the band theory of solids, which has been recently applied to the nuclear context. Using this novel approach, it is shown that the unbound neutrons move in the crust as if their mass was increased.