Unitarity in Dirichlet Higgs Model

Abstract

We show that a five dimensional Universal Extra Dimension model, compactified on a line segment, is consistently formulated even when the gauge symmetry is broken solely by non-zero Dirichlet boundary conditions on a bulk Higgs field, without any quartic interaction. We find that the longitudinal W+W- elastic scattering amplitude, under the absence of the Higgs zero-mode, is unitarized by exchange of infinite towers of KK Higgs bosons. Resultant amplitude scales linearly with the scattering energy, exhibiting five dimensional nature. A tree-level partial-wave unitarity condition is satisfied up to 6.7 (5.7) TeV for the KK scale 430 (500) GeV, favored by the electroweak data within 90% CL.

14pages, 2 figures (v1); References added (v2); Trivial error corrected: u -> t and \cosθ-> -\cosθ, references added (v3); comments added, a reference added, version to appear in Eur. Phys. J. C (v4); Expressions matched to EPJC style, obsolete affiliation (on leave) has been removed (v5)

References in corpus (5)

• Unitarity, BRST Symmetry and Ward Identities in Orbifold Gauge Theories
• NDA and perturbativity in Higgsless models
• Little Higgs, Non-standard Higgs, No Higgs and All That
• Higgsless Models: Lessons from Deconstruction
• Geometric cross sections of rotating strings and black holes

Cited by in corpus (8)

• A bound on Universal Extra Dimension Models from up to 2fb^{-1} of LHC Data at 7TeV
• Quark mass hierarchy and mixing via geometry of extra dimension with point interactions
• $CP$ phase from twisted Higgs vacuum expectation value in extra dimension
• Realization of lepton masses and mixing angles from point interactions in an extra dimension
• Heavy Higgs at Tevatron and LHC in Universal Extra Dimension Models
• Higgs production and decay processes via loop diagrams in various 6D Universal Extra Dimension Models at LHC
• Separate seesaw and its applications to dark matter and baryogenesis
• Active Dirac Neutrinos via $SU(2{)}_L$ Doublets in 5d