Theoretical and observational constraints on the mass-radius relations of neutron stars

TL;DR

This paper combines theoretical models and observational data to constrain the mass-radius relationships of neutron stars, highlighting the preference for stiff equations of state based on current observations.

Contribution

It introduces a comprehensive approach considering multiple fundamental interactions and stability criteria to refine neutron star mass-radius bounds.

Findings

Observational constraints favor stiff equations of state.

Calculated upper and lower bounds for neutron star parameters.

Theoretical models align with observational data.

Abstract

We investigate theoretical and observational constraints on the mass-radius relations for neutron stars. For that purpose we consider the model of neutron stars taking into considerations strong, weak, electromagnetic and gravitational interactions in the equation of state and integrate the structure equations within the Hartle-Thorne formalism for rotating configurations. On the basis of the theoretical restrictions imposed by general relativity, mass-shedding and axisymmetric secular instabilities we calculate the upper and lower bounds for the parameters of neutron stars. Our theoretical calculations have been compared and contrasted with the observational constraints and as a result we show that the observational constraints favor stiff equations of state.