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Measurement of the Running of the Electromagnetic Coupling at LEP

Salvatore Mele
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Abstract

The study of low-angle and large-angle Bhabha scattering at LEP gives access to the running of the electromagnetic coupling. Two recent measurements of the OPAL and L3 collaborations probe the running of alpha in the regions 1.8GeV^2<-Q^2<6.1GeV^2 and 1800GeV^2 <-Q^2 <21600GeV^2, respectively. The strategies and the results of these studies are presented. A global overview is given of the agreement of these and previous L3 findings with the QED predictions.

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Salvatore Mele. 2006-01-30. Measurement of the Running of the Electromagnetic Coupling at LEP. https://arxiv.org/abs/hep-ex/0601045

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