Heavy quark free energies and screening at finite temperature and density

TL;DR

This paper investigates how heavy quark free energies and screening effects behave at finite temperature and density in 2-flavour QCD, using lattice simulations with improved staggered fermions and Taylor expansion for baryon density.

Contribution

It provides the first lattice QCD study of heavy quark free energies at finite density, including the mu-dependence of Debye screening masses.

Findings

Debye masses increase with temperature above Tc

Finite baryon density affects screening lengths

Results agree qualitatively with perturbative predictions

Abstract

We study the free energies of heavy quarks calculated from Polyakov loop correlation functions in full 2-flavour QCD using the p4-improved staggered fermion action. A small but finite Baryon number density is included via Taylor expansion of the fermion determinant in the Baryo-chemical potential mu. For temperatures above Tc we extract Debye screening masses from the large distance behaviour of the free energies and compare their mu-dependence to perturbative results.