Two - pion contribution to the muon magnetic moment 1
نویسنده
چکیده
The two-pion contribution to hadronic vacuum polarization can be extracted from τ decay data when isospin violating and radiative corrections are taken into account. When the dominant corrections are applied to the photon-inclusive decay τ− → ντπ π[γ], one obtains a shift ∆aμ = (−12.0± 2.6)× 10 −10 for the anomalous magnetic moment of the muon. The shift appears to be too small to reconcile the determinations of hadronic vacuum polarization from existing τ and ee data. The reliability of electromagnetic corrections in the photon-inclusive τ decay is examined.
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