Study of dimuon pair production in e+ e- collisions from 196 - 202 GeV

In this thesis the electroweak process $e^{+} e^{-}$ --> $μ^{+} μ^{-}$ was studied and an inclusive and exclusive cross section were measured. Furthermore the forward-backward asymmetry Afb was determined from the exclusive event sample. The investigated data was recorded·with the detector ALEPH at centre-of-mass energies of 196, 200 and 202 GeV resulting in a total integrated luminosity of 208.1 pb-1. All the measured results are in good agreement with the Standard Model. From the measurements of total cross sections and angular distributions for all the two fermion processes at energies from 130 - 202 GeV limits on processes beyond the Standard Model were derived. For Contact Interactions they were found to be of the order of 10 TeV while for TeV-Scale Quantum Gravity a limit for the ultra-violet cut-off parameter of A::1 TeV could be derived.