QCD thermodynamics with effective models

TL;DR

This paper extends the Polyakov-quark-meson model to include 2+1 quark flavors, analyzes its thermodynamics at finite temperature and chemical potential, and compares results with lattice QCD simulations, using advanced differentiation techniques.

Contribution

It introduces a novel algorithmic differentiation method to compute high-order Taylor coefficients in the model, enabling detailed convergence analysis.

Findings

Model results agree with recent lattice QCD data.

First calculation of 24th order Taylor coefficients in this context.

Insights into the convergence properties of the Taylor expansion.

Abstract

In this talk we extend the Polyakov-quark-meson model to N_f=2+1 quark flavors and study its bulk thermodynamics at finite temperatures in mean-field approximation. Three different Polyakov-loop potentials are considered. Our findings are confronted to recent QCD lattice simulations of the RBC-Bielefeld and HotQCD collaborations. Furthermore, the finite chemical potential expansion of the quark-number susceptibility in a Taylor series around vanishing chemical potential is analyzed. By means of a novel algorithmic differentiation technique, we have calculated Taylor coefficients up to 24th order in the model for the first time. This allows the systematic study of convergence properties of the Taylor series.