A phenomenological study of 5d supersymmetry

Abstract

Supersymmetry and extra dimension need not be mutually exclusive options of physics for the TeV scale and beyond. In this paper, we envisage a phenomenological scenario by embedding the 4d constrained minimal supersymmetric standard model in a flat 5d $S_1 /Z_2$ orbifold, with the inverse radius of compactification at the TeV scale. The gauge, Higgs and the third generation matter multiplets are placed in the bulk. From a 4d perspective, the bulk has N=2 supersymmetry which entails a special non-renormalization theorem giving rise to a significant numerical impact on the renormalization group running of various parameters. The brane supersymmetry corresponds to N=1 which we assume to be broken in an unspecified but phenomenologically acceptable way. Given this set-up, we study how the gauge and Yukawa couplings and the N=1 brane supersymmetry breaking soft masses run through the energy scale exciting the Kaluza-Klein states at regular interval. We present our results by showing the allowed/disallowed zone in the plane of the common scalar mass ($m_0$) and common gaugino mass ($M_{1/2}$). Our plots are the first 5d versions of the often displayed 4d $m_0$--$M_{1/2}$ plots, and we provide reasons behind the differences between the 4d and 5d plots.