Decays of weak vector bosons and t quarks into doubly charged Higgs scalars

We evaluate the decays of W+ and Z0 bosons into chi++, the doubly charged member of the scalar triplet in the Gelmini-Roncadelli model in which spontaneously broken B-L symmetry gives Majorana masses to neutrinos. For M(chi++)<28 GeV, the branching fractions exceed 4% for W+→chi++chi- and 2% for Z0→chi++chi--. Sequential chi++→l1+l2+ leptonic decays could be substantially higher than previously recognized and could be dominant. Decay distributions for leptons of this origin are calculated for p-barp colliders. We also evaluate t→bchi++chi- decay