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arXiv · 1511.04751

Study of the hadronic contributions to the running of the QED coupling and the weak mixing angle

Anthony Francis·Vera Gülpers·Gregorio Herdoíza·Hanno Horch·Benjamin Jäger·Harvey B. Meyer·Hartmut Wittig
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Abstract

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.

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Anthony Francis, Vera Gülpers, Gregorio Herdoíza, Hanno Horch, Benjamin Jäger, Harvey B. Meyer, Hartmut Wittig. 2015-11-15. Study of the hadronic contributions to the running of the QED coupling and the weak mixing angle. https://arxiv.org/abs/1511.04751

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