# Constraining the neutron star equation of state using multi-band independent measurements of radii and tidal deformabilities

## TL;DR

This paper combines gravitational wave and X-ray observations using Bayesian methods to tightly constrain the neutron star equation of state, improving radius bounds over previous studies.

## Contribution

It introduces a joint Bayesian analysis of multi-band measurements to derive more precise neutron star EoS constraints.

## Key findings

- Tighter radius constraints than previous bounds.
- Consistent EoS parameters with multi-band data.
- Improved understanding of matter at supranuclear densities.

## Abstract

Using a Bayesian approach, we combine measurements of neutron star macroscopic observables obtained by astrophysical and gravitational observations, to derive joint constraints on the equation of state (EoS) of matter at supranuclear density. In our analysis we use two sets of data: (i) the masses and tidal deformabilities measured in the binary neutron star event GW170817, detected by LIGO and Virgo; (ii) the masses and stellar radii measured from observations of nuclear bursts in accreting low-mass X-ray binaries. Using two different parametrizations of the equation of state, we compute the posteriorprobability distributions of the EoS parameters, using which we infer the posterior distribution for the radius and the mass of the two neutron stars of GW170817. The constraints we set on the radii are tighter than previous bounds.