5D SUSY Orbifold SU(6) GUT and Pseudo-Goldstone Higgs Doublets

Abstract

We construct a 5D SUSY SU(6) GUT on an $S^{(1)}/Z_2\tm Z_2'$ orbifold. The first stage of gauge symmetry breaking occurs through compactification and a specific selection of boundary conditions. Additional symmetries play a crucial role for the generation of $\mu$ and $B\mu$ terms of appropriate values: with a $SU(2{)}_{cus}$ custodial symmetry the Higgs doublets naturally emerge as massless pseudo-Goldstone bosons in the unbroken SUSY limit. After SUSY breaking they get masses of the order of the weak scale. If instead of $SU(2{)}_{cus}$ a discrete $Z_5$ symmetry is applied the Higgs doublet's masses are still adequately suppressed, but they are not pseudo-Goldstones. The $Z_5$ discrete symmetry also can be very important for GUT scale generation and an all order hierarchy. Fermion masses are naturally generated and nicely blend with additional symmetries. In the considered scenario unification of the three gauge couplings occurs near $10^{16}$ GeV.

References added, to appear in Phys. Lett. B

References in corpus (5)

• Gauge Unification in Higher Dimensions
• Triplet-doublet Splitting, Proton Stability and Extra Dimension
• A Minimal S^1/(Z_2 x Z_2') Orbifold GUT
• Split Multiplets, Coupling Unification and Extra Dimension
• Flat directions, doublet-triplet splitting, the monopole problem, and all that

Cited by in corpus (14)

• Dynamical Rearrangement of Gauge Symmetry on the Orbifold S^1/Z_2
• Boundary conditions as constraints
• Unification of Gauge, Higgs and Matter in Extra Dimensions
• Gauge Higgs Unification in the Left-Right Model
• E6 inspired SUSY models with exact custodial symmetry
• Some consequences of a Higgs triplet
• Grand Unification in the Projective Plane
• E6 inspired composite Higgs model
• Orbifold Breaking of 3-3-1 Model
• Neutrino Democracy And Other Phenomenology From 5D SO(10)
• Neutrino Democracy, Fermion Mass Hierarchies And Proton Decay From 5D SU(5)
• Orbifold Reduction Of The Quark-Lepton Symmetric Model
• Minimal Nambu-Goldstone Higgs Model in Supersymmetric SU(5) Revisited
• Precursors From $S^{(1)}/Z_2\tm Z_2'$ Orbifold GUTs