1997/11/12 by M. Davier, Michel Davier, A. Hoecker +2 · 1 citation
Physics and Astronomy · #Annihilation #Anomalous magnetic dipole moment #Electron #Electron–positron annihilation #Electroweak interaction #Hadron #Higgs boson #High-Energy Particle Collisions Research #Lepton #Muon #Nuclear physics #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum Chromodynamics and Particle Interactions #Vacuum polarization #Weinberg angle #hep-ph
paper · pdf · doi:10.1016/s0370-2693(97)01512-8
published as Phys.Lett. B419 (1998) 419-431 · tex, 18 pages and 3 figures
arxiv created 1997/11/12 · openalex publication_date 1998/02/01 · arxiv updated 2016/02/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We reevaluate the hadronic contribution to the running of the QED fine structure constant alpha(s) at s = MZ2. We use data from e+e- annihilation and tau decays at low energy and at the qq-bar thresholds, where resonances occur. Using so-called spectral moments and the Operator Product Expansion (OPE), it is shown that a reliable theoretical prediction of the hadronic production rate R(s) is available at relatively low energies. Its application improves significantly the precision on the hadronic vacuum polarization contribution. We obtain deltaalphahad = (277.8 +/- 2.6) x 10-4 yielding alpha-1(MZ2) = 128.923 +/- 0.036. Inserting this value in a global electroweak fit using current experimental input, we constrain the mass of the Standard Model Higgs boson to be MHiggs = (129 +103 -62) GeV. Analogously, we improve the precision of the hadronic contribution to the anomalous magnetic moment of the muon for which we obtain amuhad = (695.1 +/- 7.5) x 10-10.