Leptonic and hadronic corrections to mass and propagator of W and Z bosons

Using the propagator formalism we establish more precisely the effects of fermion loops on the boson mass ratio M2sub(W)/M2sub(Z) cos2 theta and on the energy dependence of the form factors associated to time-like or space-like W, Z and γ exchanges. We calculate the corrections due to higher doublets of quarks including vector meson formation and to higher doublets of leptons for example a large number of neutrino types. (orig.)