A Constrained Standard Model from a Compact Extra Dimension

Abstract

A SU(3) \times SU(2) \times U(1) supersymmetric theory is constructed with a TeV sized extra dimension compactified on the orbifold S^1/(Z_2 \times Z_2'). The compactification breaks supersymmetry leaving a set of zero modes which correspond precisely to the states of the 1 Higgs doublet standard model. Supersymmetric Yukawa interactions are localized at orbifold fixed points. The top quark hypermultiplet radiatively triggers electroweak symmetry breaking, yielding a Higgs potential which is finite and exponentially insensitive to physics above the compactification scale. This potential depends on only a single free parameter, the compactification scale, yielding a Higgs mass prediction of 127 \pm 8 GeV. The masses of the all superpartners, and the Kaluza-Klein excitations are also predicted. The lightest supersymmetric particle is a top squark of mass 197 \pm 20 GeV. The top Kaluza-Klein tower leads to the ρparameter having quadratic sensitivity to unknown physics in the ultraviolet.

Figures (6)

• Figure 1: $S^1 / (Z_2 \times Z_2')$ orbifold in the fifth dimension.
• Figure 2: Quantum numbers of the matter, Higgs and gauge multiplets under the two orbifoldings $y \rightarrow -y$ and $y' \rightarrow -y'$.
• Figure 3: Tree-level KK mass spectrum of the matter, Higgs and gauge multiplets.
• Figure 4: One-loop diagrams contributing to the mass squared of the Higgs boson.
• Figure 5: The Higgs potential $V$ normalized by the compactification radius $R$, as a function of $R H \equiv R |\phi_H|$. Dashed, dot-dashed and solid lines represent $V_t$, $V_H \equiv V_{H,0} + V_t$ and $V_H$ with a gauge quadratic term, respectively.