Inclusive hadronic decay rate of the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi>τ</mml:mi></mml:mrow></mml:math> lepton from lattice QCD

Abstract

The authors express the inclusive hadronic decay rate of the tau lepton as an integral over the spectral density of the two-point correlator of the weak $V\ensuremath{-}A$ hadronic current which they compute fully nonperturbatively in lattice QCD. In a lattice QCD computation with all systematic errors except for isospin breaking effects under control, they then obtain the CKM matrix element ${V}_{u\phantom{\rule{0}{0ex}}d}$ with subpercent errors showing that their nonperturbative method can become a viable alternative to superallowed nuclear beta decays for obtaining ${V}_{u\phantom{\rule{0}{0ex}}d}$.

Topics & Concepts