Equation of state constraints from nuclear physics, neutron star masses, and future moment of inertia measurements

TL;DR

This paper investigates how combining microscopic nuclear physics calculations with astrophysical observations, including future moment of inertia measurements, can refine the constraints on the neutron star equation of state and radii.

Contribution

It extends previous EOS constraints by incorporating new models and demonstrates the potential of moment of inertia data to improve neutron star property estimates.

Findings

Moment of inertia measurements can significantly tighten EOS constraints.

Using multiple models enhances the robustness of neutron star radius predictions.

Future observations are crucial for reducing uncertainties in neutron star physics.

Abstract

We explore constraints on the equation of state (EOS) of neutron-rich matter based on microscopic calculations up to nuclear densities and observations of neutron stars. In a previous work we showed that predictions based on modern nuclear interactions derived within chiral effective field theory and the observation of two-solar-mass neutron stars result in a robust uncertainty range for neutron star radii and the EOS over a wide range of densities. In this work we extend this study, employing both the piecewise polytrope extension from Hebeler et al. as well as the speed of sound model of Greif et al., and show that moment of inertia measurements of neutron stars can significantly improve the constraints on the EOS and neutron star radii.