The single-W production mechanism is synonymous to the electron-positron
annihilation into electron, neutrino and a W boson with the outgoing electron
lost in a small cone around the beam direction. It requires a Renormalization
Scheme that preserves gauge invariance and fermion masses cannot be neglected
in the calculation. A recently proposed generalization of the so-called
Fermion-Loop scheme is applied to the evaluation of observables at LEP 2
energies. Single-W processes are dominated by a regime of low momentum transfer
of the outgoing electron and any high-energy Renormalization Scheme fails to
give the correct description of the scale. The Fermion-Loop scheme
automatically converts all couplings of the theory into couplings that are
running at the appropriate scale. Therefore, in addition to represent the only
scheme fully justified on a field-theoretical basis, the Fermion-Loop is the
best starting point to include radiative corrections into single-W production.
Numerical results are presented, showing a decrease in the predictions that can
be sizeable. There is no naive and overall rescaling of the e.m. coupling
constant, in any pragmatic scheme, that can reproduce the Fermion-Loop results,
at the requested accuracy, for all configurations and for all kinematical cuts.Comment: 27 pages(Latex), 7 figure
