On the Difference between FOPT and CIPT for Hadronic Tau Decays

Abstract

In this article we review the results of our recent work on the difference between the Borel representations of tau hadronic spectral function moments obtained with the CIPT and FOPT methods. For the presentation of the theoretical results we focus on the large-${\beta }_0$ approximation, where all expressions can be written down in closed form, and we comment on the generalization to full QCD. The results may explain the discrepancy in the behavior of the FOPT and CIPT series that has been the topic of intense discussions in previous literature and which represents a major part of the theoretical uncertainties in current strong coupling determinations from hadronic tau decays. The findings also imply that the OPE corrections for FOPT and CIPT differ and that the OPE corrections for CIPT do not have standard form.

21 pages, 5 figures; contribution to EPJ ST "Renormalons and Hyperasymptotics in QCD"; conclusions extended, final journal version

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Cited by in corpus (7)

• FLAG Review 2021
• Semileptonic tau decays beyond the Standard Model
• Reconciling the Contour-Improved and Fixed-Order Approaches for $\tau$ Hadronic Spectral Moments I: Renormalon-Free Gluon Condensate Scheme
• Determination of perturbative QCD coupling from ALEPH $\tau$ decay data using pinched Borel-Laplace and Finite Energy Sum Rules
• Violations of Quark-Hadron Duality in Low-Energy Determinations of ${\alpha }_s$
• Borel-Laplace Sum Rules with $\tau$ decay data, using OPE with improved anomalous dimensions
• Reconciling the FOPT and CIPT Predictions for the Hadronic Tau Decay Rate