Constraining the Nuclear Equation of State from Rotating Neutron Stars

TL;DR

This paper develops a Bayesian framework to constrain the nuclear equation of state using observables from rotating neutron stars, incorporating rotational effects and oscillation modes for improved accuracy.

Contribution

It introduces a unified Bayesian method that combines multiple neutron star measurements, including rotation and oscillation data, to better constrain the nuclear equation of state.

Findings

Few high-precision measurements can tightly constrain the EOS.

The framework effectively incorporates rotational effects.

It demonstrates improved EOS constraints with combined observables.

Abstract

We demonstrate how observables of slowly rotating neutron stars can be used to constrain the nuclear equation of state. By building a Bayesian framework we demonstrate how combining different types of neutron star measurements, motivated by the upcoming multi-messenger era, provide informative posterior distributions of commonly used equation of state parametrizations. Exemplarily, we chose the Read et al. four parameter model that is widely used to represent realistic equations of states in neutron star physics. Since future observational campaigns will not only provide mass, radius and rotation rate measurements, but also neutron star oscillation modes, a unified framework to analyze the joint knowledge becomes necessary. While several attempts exist in the literature, the here presented framework explicitly takes into account rotational effects by using state-of-the-art universal relations for their oscillation spectra. To demonstrate its performance we apply it to observables that take into account rotational effects to best possible precision and use our independent model for the reconstruction. Only a few high precision neutron star measurements are required to put tight constraints on the underlying equation of state.