Fluctuations in the vicinity of the phase transition line for two flavor QCD

TL;DR

This paper investigates fluctuations of quark, isospin, and electric charge susceptibilities near the phase transition in two-flavor QCD using lattice simulations, providing insights into the equation of state at high temperature and density.

Contribution

It presents a detailed lattice QCD analysis of susceptibilities up to sixth order derivatives with respect to chemical potential, extending understanding of QCD thermodynamics near the phase transition.

Findings

Susceptibilities vary with temperature and chemical potential.

Hadron resonance gas model explains results below T_c.

Taylor series approach estimates susceptibilities at finite density.

Abstract

We study the susceptibilities of quark number, isospin number and electric charge in numerical simulations of lattice QCD at high temperature and density. We discuss the equation of state for 2 flavor QCD at non-zero temperature and density. Derivatives of $\ln Z$ with respect to quark chemical potential $(\mu_q)$ are calculated up to sixth order. From this Taylor series, the susceptibilities are estimated as functions of temperature and $\mu_q$. Moreover, we comment on the hadron resonance gas model, which explains well our simulation results below $T_c$.