2+1 flavors QCD equation of state at zero temperature within Dyson-Schwinger equations

TL;DR

This paper uses Dyson-Schwinger equations to analyze the equation of state and quark densities for 2+1 flavor QCD at zero temperature, revealing critical chemical potentials and stability differences.

Contribution

It provides a detailed study of the 2+1 flavor QCD EOS and quark densities using DSEs, including stability analysis and implications for QCD phase transitions and compact stars.

Findings

Identification of critical chemical potentials for quark flavors

Demonstration that 2+1 flavor system is more stable than 2 flavor system

Analysis of quark number densities, pressure, and energy density at zero temperature

Abstract

Within the framework of Dyson-Schwinger equations (DSEs), we discuss the equation of state (EOS) and quark number densities of 2+1 flavors, that is to say, $u$, $d$, and $s$ quarks. The chemical equilibrium and electric charge neutrality conditions are used to constrain the chemical potential of different quarks. The EOS in the cases of 2 flavors and 2+1 flavors are discussed, and the quark number densities, the pressure, and energy density per baryon are also studied. The results show that there is a critical chemical potential for each flavor of quark, at which the quark number density turns to nonzero from 0; and furthermore, the system with 2+1 flavors of quarks is more stable than that with 2 flavors in the system. These discussion may provide some useful information to some research fields, such as the studies related to the QCD phase transitions or compact stars.