Determination of the \(e^ + e^- \to \gamma \gamma (\gamma)\) cross-section at LEP 2

  • The DELPHI Collaboration
experimental physics

Abstract.

A test of the benchmark QED process \(e^ + e^- \to \gamma \gamma (\gamma)\) 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 \(e^ + e^- \to \gamma \gamma (\gamma)\) 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.

Keywords

Field Theory Elementary Particle Lower Limit Quantum Field Theory Particle Acceleration 

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© Springer-Verlag Berlin/Heidelberg 2004

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  • The DELPHI Collaboration

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