Abstract
We discuss the determination of the strong coupling or, equivalently, the QCD parameter. Its determination requires the use of perturbation theory in in some scheme and at some energy scale . The higher the scale , the more accurate perturbation theory becomes, owing to asymptotic freedom. As one step in our computation of the parameter in three-flavor QCD, we perform lattice computations in a scheme that allows us to nonperturbatively reach very high energies, corresponding to and below. We find that (continuum) perturbation theory is very accurate there, yielding a 3% error in the parameter, while data around are clearly insufficient to quote such a precision. It is important to realize that these findings are expected to be generic, as our scheme has advantageous properties regarding the applicability of perturbation theory.
- Received 22 April 2016
DOI:https://doi.org/10.1103/PhysRevLett.117.182001
Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.
Published by the American Physical Society