Symanzik flow on HISQ ensembles

TL;DR

This paper uses gradient-flow techniques to determine the lattice scale on HISQ ensembles, extrapolating to the continuum and physical quark masses, providing a preliminary physical scale and autocorrelation estimates.

Contribution

It introduces a scale determination method using Symanzik flow on HISQ ensembles and compares results with other groups, including systematic error analysis.

Findings

Preliminary physical scale $w_0$ determined with systematic errors.

Autocorrelation lengths estimated as a function of flowtime.

Results compared with other lattice QCD groups.

Abstract

We report on a scale determination with gradient-flow techniques on the $N_f = 2 + 1 + 1$ HISQ ensembles generated by the MILC collaboration. The lattice scale $w_0/a$, originally proposed by the BMW collaboration, is computed using Symanzik flow at four lattice spacings ranging from 0.15 to 0.06 fm. With a Taylor series ansatz, the results are simultaneously extrapolated to the continuum and interpolated to physical quark masses. We give a preliminary determination of the scale $w_0$ in physical units, along with associated systematic errors, and compare with results from other groups. We also present a first estimate of autocorrelation lengths as a function of flowtime for these ensembles.