Phase diagram and compact stars in a holographic QCD model

TL;DR

This paper employs a holographic QCD model to analyze the phase diagram and properties of compact stars, deriving an equation of state that can describe hybrid stars and extend to astrophysical contexts.

Contribution

It introduces an analytic equation of state from a holographic QCD model and applies it to study the structure of hybrid stars using TOV equations.

Findings

Existence of a critical point in the phase diagram.

Derived an analytic equation of state for quark matter.

Reproduces expected properties of hybrid stars.

Abstract

A holographic model is used to investigate the thermodynamics and the phase diagram of a heavy quarks system. From such a model we obtain an equation of state and explore its applicability in astrophysical conditions. For this objective, we work in the context of the Einstein-Maxwell-Dilaton (EMD) holographic model for quantum chromodynamics (QCD). At first, we show the existence of a critical point where the first-order transitions line ends, later on, we calculated an analytic expression for the equation of state. Additionally, with the aim of investigating the global properties of compact stars, such as the total gravitational mass and radius, the equation of state is used to solve the Tolman-Oppenheimer-Volkov (TOV) equations for stellar structure. The numerical results show that our equation of state is able to reproduce the expected behavior of hybrid stars. Our main conclusion is that, by using an equation of state emerging in the framework of the EMD holographic model for QCD, it is possible to obtain quark matter properties and that it is also possible to extend the procedure to astrophysical applications.