Related papers: Tau Decay Determination of the QCD Coupling
Details are provided how GAPP evaluates the strong coupling constant from Z and tau decays and the corresponding uncertainties.
Three important QCD-related aspects of the $\tau$ and $\mu$ dynamics are reviewed: the determination of the strong coupling from the hadronic tau decay width, leading to the updated value $\alpha_s(m_\tau^2) = 0.331 \pm 0.013$; the…
The evolution of the determination of the strong coupling constant $\alpha_s$ from the leptonic branching ratios, the lifetime, and the invariant mass distributions of the hadronic final state of the $\tau$ lepton over the last two decades…
The QCD coupling appears in the perturbative expansion of the current-current two-point (vacuum polarization) function. Any lattice calculation of vacuum polarization is plagued by several competing non-perturbative effects at small momenta…
We discuss the quantitative impact of duality violations on the determination of the strong coupling constant from hadronic tau decays, based on a preliminary analysis of OPAL data.
The pure leptonic or semileptonic character of tau decays makes them a good laboratory to test the structure of the weak currents and the universality of their couplings to the gauge bosons. The hadronic tau decay modes constitute an ideal…
Being a determination at low energies, the analysis of hadronic tau decay data provides a rather precise determination of the strong coupling alpha_s after evolving the result to M_Z. At such a level of precision, even small…
The total $\tau$ hadronic width can be accurately calculated using analyticity and the operator product expansion. The theoretical analysis of this observable is updated to include all available perturbative and non-perturbative…
The two highest precision determinations of alpha_s(M_Z^2), that based on the analysis of short-distance-sensitive lattice observables, and that based on an analysis of hadronic tau decay data, have, until very recently, given results which…
While the idea of using the operator product expansion (OPE) to extract the strong coupling from hadronic $\tau$ decay data is not new, there is an ongoing controversy over how to include quark-hadron "duality violations" (i.e., resonance…
The status of determinations of $\al_s$ from quarkonia using lattice QCD is reviewed. We compare the results with those obtained from perturbative QCD.
Recently, we extracted the strong coupling, $\alpha_s(m_\tau^2)$, from the revised ALEPH data for non-strange hadronic tau decays. Our analysis is based on a method previously used for the determination of the strong coupling from OPAL…
The QCD coupling, $\alpha_s$, is not a physical observable since it depends on conventions related to the renormalization procedure. Here we discuss a redefinition of the coupling where changes of scheme are parametrised by a single…
We study a functional method to extract the V-A condensate of dimension 6 from a comparison of tau-decay data with the asymptotic space-like QCD prediction. Our result is in agreement within errors with that from conventional analyses based…
We review the present status in the determination of the $accurate$ value of $\alpha_s$ from $\tau$-decays, where we discuss in detail the different sources of theoretical errors.
The `XIIIth Quark Confinement and the Hadron Spectrum' conference (Confinement 2018) contained a `Round Table Discussion' on the status of the determinations of the strong coupling $\alpha_s(m_Z)$ as well as prospects for future…
The compatibility of theoretically calculated values for the strong coupling constant,through the renormalization group approach with experimental data is studied. There exist considerable divergence in-between theoretical and experimental…
Precise measurements of the lepton properties provide stringent tests of the Standard Model and accurate determinations of its parameters. We overview the present status of tau physics, highlighting the most recent developments, and discuss…
The current phenomenological determinations of $\alpha_s(M_\tau)$ and $\alpha_s(M_Z)$ are shown to be only marginally consistent with the QCD evolution of the strong coupling constant between $M_Z$ and $M_\tau$. This motivates a revised…
We review the determination of the strong coupling alpha_s from the comparison of the perturbative expression for the Quantum Chromodynamics static energy with lattice data. We collect here all the perturbative expressions needed to…