A new evaluation of the hadronic vacuum polarisation contributions to the muon anomalous magnetic moment and to α(mZ2)\mathbf{\boldsymbol\alpha(m_Z^2)}

Jul 31, 2019
13 pages
Published in:
  • Eur.Phys.J.C 80 (2020) 3, 241,
  • Eur.Phys.J.C 80 (2020) 5, 410 (erratum)
  • Published: Mar 14, 2020
e-Print:

Citations per year

20032009201520212025050100150
Abstract: (Springer)
We reevaluate the hadronic vacuum polarisation contributions to the muon magnetic anomaly and to the running of the electromagnetic coupling constant at the Z-boson mass. We include newest e+ehadronse^+e^- \rightarrow \mathrm{hadrons} cross-section data together with a phenomenological fit of the threshold region in the evaluation of the dispersion integrals. The precision in the individual datasets cannot be fully exploited due to discrepancies that lead to additional systematic uncertainty in particular between BABAR and KLOE data in the dominant π+π\pi ^+\pi ^- channel. For the muon (g2)/2(g-2)/2, we find for the lowest-order hadronic contribution (694.0±4.0)1010(694.0 \pm 4.0)\cdot 10^{-10}. The full Standard Model prediction differs by 3.3σ3.3\sigma from the experimental value. The five-quark hadronic contribution to α(mZ2)\alpha (m_Z^2) is evaluated to be (276.0±1.0)104(276.0\pm 1.0)\cdot 10^{-4}.
Note:
  • 13 pages, 9 figures and 2 tables, published version in EPJ-C. arXiv admin note: substantial text overlap with arXiv:1706.09436
  • vacuum polarization: hadronic
  • muon: magnetic moment
  • coupling constant
  • electromagnetic
  • dispersion
  • anomaly
  • hadron
  • KLOE