https://doi.org/10.1051/epjconf/201817901016
Hadronic Leading Order Contribution to the Muon g-2
1
KEK Theory Center, Tsukuba, Ibaraki, 305-0801 Japan
2
Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto, 606-8502, Japan
* e-mail: dnomura@post.kek.jp
Published online: 23 May 2018
We calculate the Standard Model (SM) prediction for the muon anomalous magnetic moment. By using the latest experimental data for e+e- → hadrons as input to dispersive integrals, we obtain the values of the leading order (LO) and the next-to-leading-order (NLO) hadronic vacuum polarisation contributions as ahad, LO VPμ = (693:27 ± 2:46) × 10-10 and ahad, NLO VP μ = (_9.82 ± 0:04) × 1010-10, respectively. When combined with other contributions to the SM prediction, we obtain aμ(SM) = (11659182:05 ± 3.56) × 10-10; which is deviated from the experimental value by Δaμ(exp) _ aμ(SM) = (27.05 ± 7.26) × 10-10. This means that there is a 3.7 σ discrepancy between the experimental value and the SM prediction. We also discuss another closely related quantity, the running QED coupling at the Z-pole, α(M2 Z). By using the same e+e- → hadrons data as input, our result for the 5-flavour quark contribution to the running QED coupling at the Z pole is Δ(5)had(M2 Z) = (276.11 ± 1.11) × 10-4, from which we obtain Δ(M2 Z) = 128.946 ± 0.015.
© The Authors, published by EDP Sciences, 2018
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