Abstract

An update of the hadronic vacuum polarisation contributions to the muon magnetic anomaly and to the running of the electromagnetic couplings constant at the $Z$-boson mass is presented. Newest $e^+e^-\to$ hadrons cross-section data mainly from the BABAR and VEPP-2000 experiments have been included. For the muon $(g-2)/2$, the lowest-order hadronic contribution is evaluated to be $(693.1\pm 3.4)\cdot 10^{-10}$, improving the precision of our previous evaluation by 21%. The full Standard Model prediction differs by 3.5 $\sigma$ from the experimental value. The five-quark hadronic contribution to $\alpha(m_Z^2)$ is evaluated to be $(276.0\pm 0.9)\cdot 10^{-4}$.

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