Simulations with dynamical HISQ quarks

TL;DR

This paper discusses the progress of simulations with four flavors of dynamical HISQ quarks, highlighting reduced lattice artifacts and methods for scale setting across different lattice spacings.

Contribution

It presents new results on the lattice spacing dependence of physical quantities using HISQ action and compares it to previous asqtad simulations, demonstrating improved accuracy.

Findings

HISQ simulations exhibit significantly smaller lattice artifacts than asqtad.

Physical quantities show consistent behavior across multiple lattice spacings.

Methods for setting the lattice scale at unphysical parameters are discussed.

Abstract

We report on the status of a program of generating and using configurations with four flavors of dynamical quarks, using the HISQ action. We study the lattice spacing dependence of physical quantities in these simulations, using runs at several lattice spacings, but with the light quark mass held fixed at two tenths of the strange quark mass. We find that the lattice artifacts in the HISQ simulations are much smaller than those in the asqtad simulations at the same lattice spacings and quark masses. We also discuss methods for setting the scale, or assigning a lattice spacing to ensembles run at unphysical parameters.