Probing non-standard bosonic interactions via W-boson pair production at lepton colliders

The process e(+)e(-) --> W+W- provides a valuable laboratory to test the Standard Model (SM) and to search for new physics. The most general helicity amplitudes for this process require the introduction of nine form-factors which we calculate in the context of SU(2) x U(1) gauge-invariant extensions of the SM. The contributions of new physics are parameterized via an effective Lagrangian constructed from the light fields. Because the mechanism of electroweak symmetry-breaking remains an open problem we consider both the effective Lagrangian with a linearly realized Higgs sector, i.e. with a light physical Higgs boson, and the effective Lagrangian which utilizes a non-linear realization of the Higgs mechanism. The use of an effective Lagrangian allows one to calculate consistently non-standard contributions to e(+)e(-) --> W+W- amplitudes as well as the non-standard contributions to other processes. We study the interplay of the low-energy and Z-pole measurements with measurements via the processes e(+)e(-) --> <(ff)over bar> and e(+)e(-) --> W+W- at LEP II or a future linear e(+)e(-) collider. Concrete relationships between operators of the linear and non-linear realizations are presented where possible. (C) 1997 Elsevier Science B.V.