The strong coupling constant from lattice QCD with N_f=2 dynamical quarks

Abstract

We compute ${\Lambda }_{\overline{MS}}$ for two flavors of light dynamical quarks using non-perturbatively $O(a)$ improved Wilson fermions. We improve on a recent calculation by employing Padé-improved two-loop and three-loop perturbation theory to convert the lattice numbers to the $\overline{MS}$ scheme.

Comments: Contribution to Lattice 2001 (matrix elements), typo corrected