The Realistic Lattice Determination of alpha_s(M_Z) Revisited

TL;DR

This paper revisits the determination of the strong coupling constant alpha_s(M_Z) using lattice QCD data, incorporating new data and analysis methods to improve accuracy and consistency, resulting in a value aligning with recent non-lattice results.

Contribution

The paper introduces a revised analysis of alpha_s(M_Z) from lattice data, using new observables and data to enhance precision and agreement with other determinations.

Findings

Final alpha_s(M_Z) = 0.1192(11), 2 sigma higher than previous estimate

Improved consistency among different lattice observables

Good agreement with recent non-lattice determinations

Abstract

We revisit the earlier determination of alpha_s(M_Z) via perturbative analyses of short-distance-sensitive lattice observables, incorporating new lattice data and performing a modified version of the original analysis. We focus on two high-intrinsic-scale observables, log(W_11) and log(W_12), and one lower-intrinsic scale observable, log(W_{12}/u_0^6), finding improved consistency among the values extracted using the different observables and a final result, alpha_s(M_Z)=0.1192(11), 2 sigma higher than the earlier result, in excellent agreement with recent non-lattice determinations and, in addition, in good agreement with the results of a similar, but not identical, re-analysis by the HPQCD Collaboration. A discussion of the relation between the two re-analyses is given, focussing on the complementary aspects of the two approaches.