Tests of quark-hadron duality in tau-decays

Abstract

An exhaustive number of QCD finite energy sum rules for $\tau$-decay together with the latest updated ALEPH data is used to test the assumption of global duality. Typical checks are the absence of the dimension $d=2$ condensate, the equality of the gluon condensate extracted from vector or axial vector spectral functions, the Weinberg sum rules, the chiral condensates of dimensions $d=6$ and $d=8$, as well as the extraction of some low-energy parameters of chiral perturbation theory. Suitable pinched linear integration kernels are introduced in the sum rules in order to suppress potential quark-hadron duality violations and experimental errors. We find no compelling indications of duality violations in hadronic $\tau$-decay in the kinematic region above $s\simeq 2.2$ GeV${}^2$ for these kernels.

arXiv commentInvited talk at the Workshop on Determination of the Fundamental Parameters in QCD. Mainz Institute of Theoretical Physics, Johannes Gutenberg University of Mainz

References in corpus (6)

• Hadronic Z- and tau-Decays in Order alpha_s^4
• Precision Tau Physics
• Update of the ALEPH non-strange spectral functions from hadronic $\tau$ decays
• The strong coupling from the revised ALEPH data for hadronic $\tau$ decays
• Low-energy constants and condensates from the tau hadronic spectral functions
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Cited by in corpus (3)

• Determination of perturbative QCD coupling from ALEPH $\tau$ decay data using pinched Borel-Laplace and Finite Energy Sum Rules
• Using improved Operator Product Expansion in Borel-Laplace Sum Rules with ALEPH $\tau$ decay data, and determination of pQCD coupling
• Phenomenology of ${\tau }^{-}\to {\pi }^{-}{\nu }_{\tau }\gamma$ using LCSR