# Phase transition and stiffer core fluid in neutron stars: Effects on stellar configurations, dynamical stability, and tidal deformability

## TL;DR

This paper explores how phase transitions and stiffer core fluids in neutron stars affect their structure, stability, and tidal deformability, with implications for interpreting gravitational wave observations like GW170817.

## Contribution

It introduces a model incorporating phase transitions and stiffer fluids in neutron star cores, analyzing their effects on observable properties and stability.

## Key findings

- Phase transition influences neutron star mass and radius.
- Stiffer core fluid affects tidal deformability and stability.
- Results align with observational data from GW170817.

## Abstract

In this work, we investigate the influence of the phase transition and a stiffer fluid in neutron stars' cores on the static equilibrium configuration, dynamical stability, and tidal deformability. For this aim, it is taken into account that the fluid in the core and the envelope follow the relativistic polytropic equation of state. We find that the phase transition and a stiffer fluid in the core will reflect in the total mass, radius, speed of sound, core radius, radial stability with a slow and rapid conversion at the interface, and tidal deformability. We also investigate the dimensionless tidal deformability $\Lambda_1$ and $\Lambda_2$ for a binary neutron stars system with chirp mass equal to GW$170817$. Finally, we contrast our results with observational data to show the role that phase transition and a stiffer core fluid could play in the study of neutron stars.