Measurements of the Running of the Electromagnetic Coupling at LEP
نویسنده
چکیده
The study of Bhabha scattering at ee colliders probes the running of the electromagnetic coupling. After early measurements by the VENUS collaboration at TRISTAN and the by L3 collaboration at LEP, two recent analyses have been performed by the OPAL and L3 collaborations. The OPAL collaboration studied highstatistics low-angle Bhabha scattering at LEP, achieving a precise determination of the running of α in the region 1.8 GeV < −Q < 6.1 GeV. The L3 collaboration investigated high-energy large-angle Bhabha scattering to first probe the region 1800 GeV < −Q < 21600 GeV. All measurements are described and a global overview of their agreement with QED predictions is given.
منابع مشابه
Measurement of the Running of the Electromagnetic Coupling at LEP
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 α in the regions 1.8 GeV < −Q < 6.1 GeV and 1800 GeV < −Q < 21600 GeV, respectively. The strategies and the results of these studies are presented. A global overview is given of the agreement o...
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