Neutron-neutron short-range correlations and their impacts on neutron stars

Due to the very nature of the nucleon-nucleon interactions, some nucleons form strongly correlated nucleon-nucleon pairs. This paper focuses on the significance of nn pairs for neutron star matter. Inspired by recent numerical and experimental advances in SRCs, we propose density-dependent nucleon momentum distributions with the isospin-asymmetry scaling parameter. We also analyze the impacts of nn pairs on the physical properties of neutron stars. Our numerical results find that nn pairs, plus np pairs, could stiffen the equation of state of neutron star matter and consequently cause a significant increase in the maximum mass of neutron stars. This work might generate a fresh viewpoint on confronting the upper limit on the maximum mass of neutron stars.(c) 2022 Elsevier B.V. All rights reserved.

Automated summary

This study focuses on the importance of nucleon-nucleon pairs in neutron star matter, proposing density-dependent nucleon momentum distributions with isospin-asymmetry scaling parameter. The analysis shows that nucleon-nucleon pairs, combined with neutron-proton pairs, could stiffen the equation of state of neutron star matter and increase the maximum mass of neutron stars significantly. This work may provide a new perspective on confronting the upper limit on the maximum mass of neutron stars.