Study of four-lepton final states in electron-positron interactions at 29 GeV

This thesis presents a study of electron-positron scattering to four light leptons. The motivations behind it are twofold. Firstly, the study is a test of the theory of electron-positron interactions to 4th order in the fine structure constant α. A deviation from the theory could indicate the existence of a heavy new particle. Secondly, a measurement of these processes may prove useful in the understanding of other QED-type reactions. The method for simulating the four-lepton processes by the Monte Carlo event generator of Berends, Daverveldt and Kleiss is described. Theoretical predictions are compared to data from the Mark II and HRS experiments at the PEP storage ring. The observed events consist of four leptons at large angles. Data for all three e+e-e+e-, e+e-μ+μ- and μ+μ-μ+μ- processes are well described by the QED Monte Carlo calculation. The various kinematical distributions are in good agreement with QED to order α4. 18 refs., 64 figs., 19 tabs