Speaker
Description
The highly improved staggered quark action (HISQ) has been in use for about two decades now in calculations ranging from the hadronic contribution to the anomalous magnetic moment of the muon to QCD thermodynamics. Large data sets have been generated that allow for well-controlled chiral-continuum extrapolations. However, a class of problems that require some form of spectral reconstruction from Euclidean correlation functions, requires anisotropic lattices with a higher resolution in the temporal direction. We report on the project of developing a framework for simulations with anisotropic highly improved staggered quarks (aHISQ). Exploring a range of anisotropies from 1 to 8 on quenched ensembles, we study the dependence of the staggered pion taste mass splittings on anisotropy for the naive staggered and aHISQ action. We discuss an empirical model that captures the main features of the aHISQ spectrum and comment on the observed qualitatively different behavior of the naive and aHISQ taste spectrum with anisotropy.