Warped higgsless models with IR-brane kinetic terms

We examine a warped higgsless SU(2)_L, × SU(2)_R × U(1)_B-L model in 5-d with IR(TeV)-brane kinetic terms. It is shown that adding a brane term for the U(1)_B-L gauge field does not affect the scale (∼ 2-3 TeV) where perturbative unitarity in W _L⁺W_L^- → W_L ⁺W_L^- is violated. This term could, however, enhance the agreement of the model with the precision electroweak data. In contrast, the inclusion of a kinetic term corresponding to the SU(2)_D custodial symmetry of the theory delays the unitarity violation in W _L^± scattering to energy scales of ̃ 6-7 TeV for a significant fraction of the parameter space. This is about a factor of 4 improvement compared to the corresponding scale of unitarity violation in the Standard Model without a Higgs. We also show that null searches for extra gauge bosons at the Tevatron and for contact interactions at LEP II place non-trivial bounds on the size of the IR-brane terms.