Related papers: The hadronic contribution to the running of the el…
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…
The electromagnetic coupling $\alpha$ and the electroweak mixing angle $\theta_{\mathrm{W}}$ are parameters of the Standard Model (SM) that enter precision SM tests and play a fundamental r\^ole in beyond SM physics searches. Their values…
We present an updated determination of the hadronic vacuum polarization contribution to the running of the electromagnetic coupling $\Delta\alpha_{\mathrm{had}}^{(5)}(-Q^2)$, and of the electroweak mixing angle in the space-like momentum…
We present results for the hadronic running of the electromagnetic coupling and the weak mixing angle from simulations of lattice QCD with $N_f=2+1$ flavours of $O(a)$-improved Wilson fermions. Using two different discretisations of the…
We present an update of our lattice QCD determination of the hadronic contribution to the running of the electromagnetic coupling, $\Delta\alpha_{\mathrm{had}}^{(5)}(-Q^2)$, and of the electroweak mixing angle in the space-like momentum…
The energy dependency (running) of the strength of electromagnetic interactions $\alpha$ plays an important role in precision tests of the Standard Model. The running of the former to the $Z$ pole is an input quantity for global electroweak…
The quark-connected leading-order hadronic contributions to the running of the electromagnetic fine structure constant, $\alpha_{\rm QED}$, and the weak mixing angle, $\theta_W$, are determined by a four-flavour lattice QCD computation with…
We present preliminary results from a lattice-QCD study of the hadronic contributions to the running of the electromagnetic coupling, $\Delta\alpha(Q^2)$, and the electroweak mixing angle, $\Delta\sin^2\theta_{W}(Q^2)$. Using $N_f = 2+1+1$…
We compute the hadronic running of the electromagnetic and weak couplings in lattice QCD with $N_{\mathrm{f}}=2+1$ flavors of $\mathcal{O}(a)$ improved Wilson fermions. Using two different discretizations of the vector current, we compute…
The contribution from hadronic vacuum polarisation effects is responsible for a large fraction of the theoretical uncertainty in the running of the QED coupling. The current level of uncertainty has become a limitation for electroweak…
We perform a new, detailed calculation of the hadronic contributions to the running electromagnetic coupling, $\bar{\alpha}$, defined on the Z particle (91 GeV). We find for the hadronic contribution, including radiative corrections,…
The running of the effective electromagnetic coupling is for many electroweak observables the dominant correction. It plays an important role for deriving constraints on the Standard Model in the context of electroweak precision…
The leading hadronic effects in electroweak theory derive from vacuum polarization which are non-perturbative hadronic contributions to the running of the gauge couplings, the electromagnetic alpha_{em}(s) and the SU(2)_L coupling…
An update is described of a model independent method to determine the hadronic contribution to the QED running coupling at the Z-boson mass scale, $\Delta\alpha_{\text{HAD}}(M_{Z}^{2})$. The major source of uncertainty is from the…
We present a new independent evaluation of the hadronic and QCD contributions to the QED running coupling \alpha(M_Z) and to the muonium hyperfine splitting \nu. We obtain: \Delta\alpha_{had}=2770(17)10^{-5} and \Delta\nu_{had}=232.5(2.5)…
We introduce a model independent method for the determination of the hadronic contribution to the QED running coupling, $\Delta\alpha_{\text{HAD}}(M_{Z}^{2})$, requiring no $e^+e^-$ annihilation data as input. This is achieved by…
We report on our update to [1] on the hadronic running of electroweak couplings from $O(a)$-improved Wilson fermions with $N_f=2+1$ flavours. The inclusion of additional ensembles at very fine lattice spacings together with a number of…
We reevaluate the hadronic part of the electromagnetic vacuum expectation value using the standard dispersion integral approach that utilizes the hadronic cross section measured in $\ee$ experiments as input. Previous analyses are based…
We critically examine the evaluation of the hadronic contribution to the running of the QED coupling, $\alpha$, from $Q^2=0$ to $Q^2=M_Z^2$. Using data for $e^+e^-\to{}$hadrons we find that $\alpha(M_Z^2)^{-1} = 128.99\pm 0.06$, as compared…
The electromagnetic coupling constant, $\alpha$, is one of the fundamental parameters of the Standard Model (SM). Its value at the Z boson mass, $\alpha(M_Z)$, is of particular interest as it enters electroweak precision tests. When running…