Hadronic Z- and tau-Decays in Order alpha_s^4

Simple item page
dc.creatorBaikov, P. A.
dc.creatorChetyrkin, K. G.
dc.creatorKühn, J. H.
dc.date2008-01-11
dc.date2008-07-04
dc.date.accessioned2026-07-07T11:55:10Z
dc.date.available2026-07-07T11:55:10Z
dc.descriptionUsing recently developed methods for the evaluation of five-loop amplitudes in perturbative QCD, corrections of order alpha_s^4 for the cross section of electron-positron annihilation into hadrons and for the decay rates of the Z-boson and the tau-lepton into hadrons are evaluated. The new terms lead to a significant stabilization of the perturbative series, to a reduction of the theory uncertainly in the strong coupling constant alpha_s, as extracted from these measurements, and to a small shift of the central value, moving two central values closer together. The agreement between two values of alpha_s measured at vastly different energies constitutes a striking test of asymptotic freedom. Combining the results from Z and tau decays we find alpha_s(M_Z)=0.1198 \pm 0.0015 as one of the most precise and presently only result for the strong coupling constant in order alpha_s^4.
dc.descriptionfew citations added, final published version
dc.identifierhttps://arxiv.org/abs/0801.1821
dc.identifierhttp://arxiv.org/abs/0801.1821
dc.identifierPhys.Rev.Lett.101:012002,2008
dc.identifierdoi:10.1103/PhysRevLett.101.012002
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/205158
dc.subjectHigh Energy Physics - Phenomenology
dc.titleHadronic Z- and tau-Decays in Order alpha_s^4
dc.typetext

Files

Collections

arXiv