Off-shell structure of the anomalous Z and γ self-couplings -: art. no. 073012

We establish the general off-shell structure of the three neutral gauge boson self-couplings V-1*V-2*V-3*, with applications to the Z*Z*Z*, Z*Z* gamma*, gamma*gamma*Z* cases. New coupling forms appear which do not exist when two gauge bosons are on shell We give the contribution arising from a fermionic triangle loop. It covers both the standard model (SM) and possible new physics (NP) contributions such as those arising in the minimal supersymmetric SM. For what concerns NP contributions with a high scale, we discuss the validity of an effective Lagrangian involving a limited set of parameters. Finally we write the general expression of the V-1*V-2*V-3*-vertex contribution to the e(+)e(-) --> (f (f) over bar) + (f'(f) over bar') amplitude.