Exact $O(\alpha )$ Gauge Invariant YFS Exponentiated Monte Carlo for (Un)Stable for (Un)Stable $W^{+}{W}^{-}$ Production At and Beyond LEP2 Energies

We realize, by Monte Carlo event generator methods, the exact O}(\alpha)$ YFS exponentiated calculation of $e^+e^- \to W^+ W^- (\to f_1\bar f’_1 + \bar f_2 f’_2)$atandbeyondLEP2energies,wheretheleft-handedpartsof$f_i$and$f’i$aretherespectiveupperandlowercomponentsofan$SU{2L}$doublet,$i=1,2$. Our calculation is gauge invariant from the standpoint of its radiative effects and the respective YFS Monte Carlo event generator YFSWW3, wherein both Standard Model and anomalous triple gauge boson couplings are allowed, generates $n(\gamma )$ radiation both from the initial state and from the final $W^{+}{W}^{-}$. Sample Monte Carlo data are illustrated.