Split supersymmetry in an orbifold GUT

Abstract

We propose a supersymmetric SU(5) orbifold GUT in 5 dimensions in which supersymmetry breaking at the boundaries gives rise to split supersymmetry spectrum. The extra dimension is compactified on a S¹/Z₂×Z'₂ orbifold having two fixed points. The standard model fermions are localized in the standard model brane, where supersymmetry is broken by the nonvanishing of the F-term of a superfield X at some intermediate scale. All scalar superpartners acquire mass at this stage. The standard model gauginos and Higgsinos remain light, since their masses are protected by R-symmetry and induced only by loop contributions and contact interaction in our brane. Usual features of orbifold GUTs are preserved in this scenario and proton decay and neutrino mass problems are solved.