PUB - Publikationen an der Universität Bielefeld

The recent precision electroweak data on GAMMA(l), s(W)2BAR and M(W)/M(Z) are compared with the tree-level and the dominant-fermion-loop as well as the full one-loop standard-model predictions. While the tree-level predictions are ruled out, the dominant-fermion-loop predictions, defined by using alpha(M(Z)2) congruent-to 1/128.9 in the tree-level formulae, as well as the full one-loop predictions are consistent with the experimental data. Deviations from the dominant-fermion-loop predictions are quantified in terms of an effective Lagrangian containing three additional parameters which have a simple meaning in terms of SU(2) symmetry violation. The effective Lagrangian yields the standard one-loop predictions for specific values of these parameters, which are determined by m(t) and M(H)