Static quarks with improved statistical precision

TL;DR

This paper investigates various discretisations of the static action in lattice QCD, demonstrating significant error reduction and improved precision in key quark parameters through optimized actions.

Contribution

It introduces improved static actions that reduce statistical errors and discretization effects, enhancing the accuracy of static quark calculations.

Findings

Error reduction by an order of magnitude for time separations beyond 1.3 fm

Significant improvement in the precision of quark mass Mb and decay constant F_Bs

Optimized actions maintain small discretization errors while reducing statistical errors

Abstract

We present a numerical study for different discretisations of the static action, concerning cut-off effects and the growth of statistical errors with Euclidean time. An error reduction by an order of magnitude can be obtained with respect to the Eichten-Hill action, for time separations beyond 1.3 fm, keeping discretization errors small. The best actions lead to a big improvement on the precision of the quark mass Mb and F_Bs in the static approximation.