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Author (up) Davier, M.; Diaz-Calderon, D.; Malaescu, B.; Pich, A.; Rodriguez-Sanchez, A.; Zhang, Z.
Title The Euclidean Adler function and its interplay with Delta alpha(had)(QED) and alpha(s) Type Journal Article
Year 2023 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 04 Issue 4 Pages 067 - 57pp
Keywords Correlation Functions; Effective Field Theories of QCD; The Strong Coupling
Abstract Three different approaches to precisely describe the Adler function in the Euclidean regime at around 2 GeVs are available: dispersion relations based on the hadronic production data in e(+)e(-) annihilation, lattice simulations and perturbative QCD (pQCD). We make a comprehensive study of the perturbative approach, supplemented with the leading power corrections in the operator product expansion. All known contributions are included, with a careful assessment of uncertainties. The pQCD predictions are compared with the Adler functions extracted from ?a( QED)(had)(Q(2)), using both the DHMZ compilation of e(+)e(-) data and published lattice results. Taking as input the FLAG value of a(s), the pQCD Adler function turns out to be in good agreement with the lattice data, while the dispersive results lie systematically below them. Finally, we explore the sensitivity to a(s) of the direct comparison between the data-driven, lattice and QCD Euclidean Adler functions. The precision with which the renormalisation group equation can be tested is also evaluated.
Address [Davier, M.; Zhang, Z.] Univ Paris Saclay, CNRS IN2P3, IJCLab, F-91405 Orsay, France, Email: davier@lal.in2p3.fr;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000985363600002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5533
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Author (up) Pich, A.; Rodriguez-Sanchez, A.
Title Violations of quark-hadron duality in low-energy determinations of alpha(s) Type Journal Article
Year 2022 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 07 Issue 7 Pages 145 - 42pp
Keywords The Strong Coupling; Semi-Leptonic Decays; Specific QCD Phenomenology; Chiral Lagrangian
Abstract 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.
Address [Pich, Antonio] Univ Valencia, Dept Fis Teor, CSIC, IFIC, Parque Cient,Catedrat Jose Beltran 2, E-46980 Paterna, Spain, Email: Antonio.Pich@ific.uv.es;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000831256400009 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5303
Permanent link to this record