https://doi.org/10.1051/epjconf/201817501018
Determination of the Strong Coupling Constant by the ALPHA Collaboration
Department of Physics, Bergische Universität Wuppertal, Gaußstr. 20, 42119 Wuppertal, Germany
* Speaker, e-mail: korzec@uni-wuppertal.de
Published online: 26 March 2018
A high precision determination of the strong coupling constant in the MS scheme at the Z-mass scale, using low energy quantities, namely pion/kaon decay constants and masses, as experimental input is presented. The computation employs two different massless finite volume renormalization schemes to non-perturbatively trace the scale dependence of the respective running couplings from a scale of about 200 MeV to 100 GeV. At the largest energies perturbation theory is reliable. At high energies the Schrödinger-Functional scheme is used, while the running at low and intermediate energies is computed in a novel renormalization scheme based on an improved gradient flow. Large volume Nf = 2 + 1 QCD simulations by CLS are used to set the overall scale. The result is compared to world averages by FLAG and the PDG.
© The Authors, published by EDP Sciences, 2018
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (http://creativecommons.org/licenses/by/4.0/).