English

$\alpha_s$ from an improved $\tau$ vector isovector spectral function

High Energy Physics - Phenomenology 2023-01-11 v1 High Energy Physics - Lattice

Abstract

After discussing difficulties in determining αs\alpha_s from tau decay due to the existence of Duality Violations and the associated asymptotic nature of the OPE, we describe a new determination based on an improved vector isovector spectral function, now based solely on experimental input, obtained by (i) combining ALEPH and OPAL results for 2π+4π2\pi +4\pi and (ii) replacing KK0K^-K^0 and higher-multiplicity exclusive-mode contributions, both previously estimated using Monte Carlo, with new experimental BaBar results for KK0K^-K^0 and results implied by e+ee^+ e^- cross sections and CVC for the higher-multiplicity modes. We find αs(mτ)=0.3077±0.0075\alpha_s(m_\tau)=0.3077\pm 0.0075, which corresponds to αs(mZ)=0.1171±0.0010\alpha_s(m_Z)=0.1171\pm 0.0010. Finally, we comment on some of the shortcomings in the criticism of our approach by Pich and Rodriguez-Sanchez.

Keywords

Cite

@article{arxiv.2210.13518,
  title  = {$\alpha_s$ from an improved $\tau$ vector isovector spectral function},
  author = {Diogo Boito and Maarten Golterman and Kim Maltman and Santiago Peris and Marcus V. Rodrigues and Wilder Schaaf},
  journal= {arXiv preprint arXiv:2210.13518},
  year   = {2023}
}

Comments

Contribution to the proceedings of The XVth Quark Confinement and the Hadron Spectrum Conference, August 1st-6th, 2022, Univ. of Stavanger, Norway

R2 v1 2026-06-28T04:23:53.922Z