Neutron stars in the Witten-Sakai-Sugimoto model

TL;DR

This paper models neutron stars using a holographic QCD approach combined with various equations of state, successfully matching observational data on neutron star masses and radii.

Contribution

It introduces a hybrid holographic QCD model calibrated to nuclear matter properties, providing accurate neutron star predictions.

Findings

Maximal neutron star masses compatible with observations

Predicted mass-radius relations match observational constraints

Model reproduces known tidal deformability data

Abstract

We utilize the top-down holographic QCD model, the Witten-Sakai-Sugimoto model, in a hybrid setting with the SLy4, soft chiral EFT and stiff chiral EFT equations of state to describe neutron stars with high precision. In particular, we employ a calibration that bootstraps the nuclear matter by fitting the Kaluza-Klein scale and the 't Hooft coupling such that the physical saturation density and physical symmetry energy are achieved. We obtain static stable neutron star mass-radius data via the Tolman-Oppenheimer-Volkov equations that yield sufficiently large maximal masses of neutron stars to be compatible with the recently observed PSR-J0952-0607 data as well as all other known radius and tidal deformation constraints.