PT Journal
AU Pich, A
   Rodriguez-Sanchez, A
TI Violations of quark-hadron duality in low-energy determinations of alpha(s)
SO Journal of High Energy Physics
JI J. High Energy Phys.
PY 2022
BP 145
EP 42pp
VL 07
IS 7
DI 10.1007/JHEP07(2022)145
LA English
DE The Strong Coupling; Semi-Leptonic Decays; Specific QCD Phenomenology; Chiral Lagrangian
AB Using the spectral functions measured in tau decays, we investigate the actual numerical impact of duality violations on the extraction of the strong coupling. These effects are tiny in the standard alpha(s)(m(tau)(2)) determinations from integrated distributions of the hadronic spectrum with pinched weights, or from the total tau hadronic width. The pinched-weight factors suppress very efficiently the violations of duality, making their numerical effects negligible in comparison with the larger perturbative uncertainties. However, combined fits of alpha(s) and duality-violation parameters, performed with non-protected weights, are subject to large systematic errors associated with the assumed modelling of duality-violation effects. These uncertainties have not been taken into account in the published analyses, based on specific models of quark-hadron duality.
ER