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arXiv · hep-ex/0409058

Determination of the e+e- -> gamma gamma (gamma) cross-section at LEP 2

The DELPHI Collaboration·J. Abdallah
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Abstract

A test of the benchmark QED process e+e- -> gamma gamma (gamma) is reported, using the data collected with the DELPHI detector at LEP 2. The data analysed were recorded at centre-of-mass energies ranging from 161 GeV to 208 GeV and correspond to a total integrated luminosity of 656.4 pb^{-1}. The Born cross-section for the process e+e- -> gamma gamma (gamma) was determined, confirming the validity of QED at the highest energies ever attained in electron-positron collisions. Lower limits on the parameters of a number of possible deviations from QED, predicted within theoretical frameworks expressing physics beyond the Standard Model, were derived.

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The DELPHI Collaboration, J. Abdallah. 2004-09-28. Determination of the e+e- -> gamma gamma (gamma) cross-section at LEP 2. https://doi.org/10.1140/epjc%2Fs2004-01990-2

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