Predictions for g − 2 of the muon and α QED ( M 2 Z )
نویسندگان
چکیده
We calculate (g − 2) of the muon and the QED coupling α(M 2 Z), by improving the determination of the hadronic vacuum polarization contributions and their uncertainties. We include the recently re-analysed CMD-2 data on e + e − → π + π −. We carefully combine a wide variety of data for the e + e − production of hadrons, and obtain the optimum form of R(s) ≡ σ 0 had (s)/σ pt (s), together with its uncertainty. Our results for the hadronic contributions to g − 2 of the muon are a had,LO
منابع مشابه
Standard Model Predictions for the Muon (g − 2)/2
where e, m and g are the charge, mass and gyromagnetic factor of the particle. In the Dirac theory of a charged pointlike spin-1/2 particle, g = 2, and QED effects slightly increase the g value. Conventionally, a quantity a ≡ (g−2)/2 is referred to as the anomalous magnetic moment. The electron and muon anomalous magnetic moments have been measured with a very high relative accuracy of 0.24 ppb...
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