Autor/a: Braaten, Eric; Narison, Stephan; Pich Zardoya, Antonio
Resum: 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 corrections. Experimental measurements of tau-decay rates are used to determine with high precision the QCD running coupling constant at the scale of the tau-mass. The analysis is also used to study the present discrepancy between the experimental measurements of the leptonic branching fractions of the tau and its total lifetime.