Chiral sum rules and vacuum condensates from tau-lepton decay data

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QCD finite energy sum rules, together with the latest updated ALEPH data on hadronic decays of the tau-lepton are used in order to determine the vacuum condensates of dimension d=2 and d=4. These data are also used to check the validity of the Weinberg sum rules, and to determine the chiral condensates of dimension d=6 and d=8, as well as the chiral correlator at zero momentum, proportional to the counter term of the O(p⁴) Lagrangian of chiral perturbation theory, L₁₀. Suitable (pinched) integration kernels are introduced in the sum rules in order to suppress potential quark-hadron duality violations. We find no compelling indications of duality violations in the kinematic region above s ≃ 2.2 GeV² after using pinched integration kernels.