English

QCD condensates and $\alpha_s$ from $\tau$-decay: Summary

High Energy Physics - Phenomenology 2025-02-20 v2 High Energy Physics - Experiment High Energy Physics - Lattice

Abstract

In this talk, I summarize the recent determinations in Ref.[1] of the QCD condensates and αs\alpha_s within the SVZ expansion using the ratio of Laplace sum rule (LSR) R10A(τ){\cal R}_{10}^A(\tau) and τ\tau-like moments Rn,A,Rn,VA{\cal R}_{n,A},\, {\cal R}_{n,V-A}within stability criteria in the axial-vector (A) and V-A channels of the τ\tau- semi-hadronic decays. The factorization of the four-quark condensate is violated by a factor 6 like in the case of the e+ee^+e^-\to Hadrons data. There is no exponential growth of the size of higher dimension condensates which does not favour (by duality) a significant effect of the so-called Duality Violation (DV). The extracted value of αs\alpha_s is in good agreement with the one from e+ee^+e^- and indicates that the determination at the observed τ\tau-mass is not the optimal one and leads to an overestimate of its actual value.

Keywords

Cite

@article{arxiv.2501.08369,
  title  = {QCD condensates and $\alpha_s$ from $\tau$-decay: Summary},
  author = {S. Narison and LUPM and iHEPMAD},
  journal= {arXiv preprint arXiv:2501.08369},
  year   = {2025}
}

Comments

Latex sources, 15 pages, 6 figures, 3 tables, Talk given at the 14th International Conference in High-Energy Physics (HEPMAD24), 21-26th October 2024, Antananarivo, MG. Version to appear in Journal of Subatomic Particles and Cosmology. arXiv admin note: substantial text overlap with arXiv:2408.05732

R2 v1 2026-06-28T21:06:25.518Z