The electromagnetic coupling receives significant contributions to its running from non-perturbative QCD effects. We present an update of a lattice QCD study of the Adler function and of its application to the determination of the running of the QED coupling. We perform a high-statistics computation with two flavours of O$(a)$ improved Wilson fermions in a large range of momentum transfer $Q^2$. The running of the electromagnetic coupling, including contributions from $u$, $d$, $s$ and $c$ valence quarks, is compared to phenomenological determinations at intermediate $Q^2$ values. An extension of this study to the determination of the hadronic contributions to the running of the weak mixing angle is also described.
|Journal||P o S - Proceedings of Science|
|Publication status||Published - 15. Nov 2015|
Bibliographical note7 pages, 5 figures. Proceedings Contribution to the 33rd International Symposium on Lattice Field Theory (Lattice 2015), 14-18 July 2015, Kobe, Japan