Phenomenology of Supersymmetric Models

Abstract

In the previous three chapters we have laid the foundation for applying the ideas of supersymmetry to building models of particle physics. At present there exists a successful (at low energies) model of electro-weak and strong interactions—the standard SU(2) _L × U(1) _Y × SU(3) _C model. The recent discovery of W- and Z-bosons at the CERN SppS machine has proved the correctness of this theory. Also, everybody believes that there is more physics beyond the standard model. In Chapters 6, 7, and 8 we have discussed some interesting classes of models that provide examples of possible new physics. In this chapter we consider the possibility that new physics may be related to supersymmetry. Specifically, if elementary scalar bosons are to be part of the unified gauge theory framework, existence of a hidden supersymmetry might not only make their field theory better “behaved” but also establish a connection between fermions and bosons. As already emphasized in such a case, supersymmetry must be broken by soft terms since we do not observe any degenerate multiplets containing bosons and fermions. In this first section we will present a supersymmetric extension of the standard model. All fermions and bosons of the standard model must be accompanied by their super-symmetric partners which are bosons and fermions, respectively.