218 articles – 617 references  [version française]
 HAL: in2p3-00023211, version 1
 arXiv: hep-ex/0409058
 European Physical Journal C 37 (2004) 405-419
 Determination of the $e^+e^- \rightarrow \gamma \gamma (\gamma)$ cross-section at LEP2
 For the DELPHI collaboration(s)
 (2004)
 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.
 Subject(s) : Physics/High Energy Physics - Experiment