Hadronic contribution to the QED running coupling $\alpha(M_{Z}^2)$
Abstract
We introduce a model independent method for the determination of the hadronic contribution to the QED running coupling, , requiring no annihilation data as input. This is achieved by calculating the heavy-quark contributions entirely in perturbative QCD, whilst the light-quark resonance piece is determined using available lattice QCD results. Future reduction in the current uncertainties in the latter shall turn this method into a valuable alternative to the standard approach. Subsequently, we find that the precision of current determinations of can be improved by some 20% by computing the heavy-quark pieces in PQCD, whilst using data only for the low-energy light-quark sector. We obtain in this case , which currently is the most precise value of .
Cite
@article{arxiv.1209.4802,
title = {Hadronic contribution to the QED running coupling $\alpha(M_{Z}^2)$},
author = {S. Bodenstein and C. A. Dominguez and K. Schilcher and H. Spiesberger},
journal= {arXiv preprint arXiv:1209.4802},
year = {2015}
}
Comments
A misprint in Eq. (6) has been corrected