Tests of quark-hadron duality in τ-decays
Abstract
An exhaustive number of QCD finite energy sum rules for τ-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 τ-decay in the kinematic region above s ≃ 2.2 GeV2 for these kernels.
- Publication:
-
Modern Physics Letters A
- Pub Date:
- September 2016
- DOI:
- 10.1142/S0217732316300366
- arXiv:
- arXiv:1607.02048
- Bibcode:
- 2016MPLA...3130036D
- Keywords:
-
- QCD;
- sum rules;
- τ-decays;
- 12.38.Lg;
- 11.55.Hx;
- 13.35.Dx;
- Other nonperturbative calculations;
- Sum rules;
- Decays of taus;
- High Energy Physics - Phenomenology;
- High Energy Physics - Experiment;
- High Energy Physics - Lattice
- E-Print:
- Invited talk at the Workshop on Determination of the Fundamental Parameters in QCD. Mainz Institute of Theoretical Physics, Johannes Gutenberg University of Mainz