First results on QCD thermodynamics with HISQ action

TL;DR

This study explores the QCD phase transition at finite temperature using the HISQ lattice action, analyzing key observables and comparing results with other improved staggered fermion formulations to understand the thermodynamics of strong interactions.

Contribution

First application of the HISQ action to finite temperature QCD thermodynamics with detailed observable calculations and comparison to other improved staggered fermion results.

Findings

HISQ results show consistent crossover behavior with previous formulations.

Calculated observables include Polyakov loop, chiral condensate, and fluctuations.

Results contribute to understanding the QCD phase diagram.

Abstract

We report on investigations of the chiral and deconfinement aspects of the finite temperature transition in 2+1 flavor QCD using the Highly Improved Staggered Quark (HISQ) action on lattices with temporal extent $N_\tau=6$ and $N_\tau=8$. We have calculated several physical observables, including the renormalized Polyakov loop, strangeness fluctuations, the renormalized chiral condensate and the chiral susceptibility in the crossover region for physical values of the strange quark mass $m_s$ and light quark masses $m_l=0.2m_s$ and $0.05m_s$. We compare our findings with previous calculations that use different improved staggered fermion formulations: asqtad, p4 and stout.