Strong coupling in (2+1+1)-flavor QCD

TL;DR

This paper determines the strong coupling constant in (2+1+1)-flavor QCD by comparing lattice calculations of static energy with perturbative theory, achieving high precision at small lattice spacings.

Contribution

It presents a new precise determination of _ in (2+1+1)-flavor QCD using state-of-the-art lattice data and perturbative calculations up to three loops.

Findings

Preliminary _(M_Z) value obtained.

Lattice spacing as small as 0.0321 fm used.

Comparison of lattice and perturbative results demonstrated consistency.

Abstract

The strong coupling $\alpha_\mathrm{s}$ can be obtained from the static energy as shown in previous lattices studies. For short distances, the static energy can be calculated both on the lattice with the use of Wilson line correlators, and with the perturbation theory up to three loop accuracy with leading ultrasoft log resummation. Comparing the perturbative expression and lattice data allows for precise determination of $\alpha_\mathrm{s}(m_Z)$. We will present preliminary results for the determination of $\alpha_\mathrm{s} {(M_Z)}$ in (2+1+1)-flavor QCD using the configurations made availableby the MILC-collaboration with smallest lattice spacing reaching 0.0321fm.