Enhanced Electroweak Corrections to Inclusive Boson Fusion Processes at the TeV Scale ∗

Electroweak radiative corrections with double-log enhancements occur in inclusive observables at the TeV scale because of a lack of compensation of virtual corrections with real emission due to the nonabelian (weak isospin) charges of the accelerator beams. Here we evaluate such Bloch-Nordsieck violating corrections in the case of initial longitudinal bosons, which is experimentally provided by boson fusion processes, and is related to the GoldstoneHiggs sector. All four states of this sector are involved in the group structure of the corrections, and cause in particular a novel double log effect due to hypercharge mixing in the longitudinal states. We study both the lightand the heavy-Higgs cases, and we analyze the symmetry breaking pattern of the corrections. The latter turn out to be pretty large, in the 5-10 % range, and show an interesting Higgs mass dependence, even for processes without Higgs boson in the final state. Work supported in part by EU QCDNET contract FMRX-CT98-0194 and by MURST (Italy).