Horizontal, anomalous U(1) symmetry for the more minimal supersymmetric standard model

We construct explicit examples with a horizontal, “anomalous” U(1) gauge group, which, in a supersymmetric extension of the standard model, reproduce qualitative features of the fermion spectrum and CKM matrix, and suppress FCNC and proton decay rates without the imposition of global symmetries. We review the motivation for such “more” minimal supersymmetric standard models and their predictions for the sparticle spectrum. There is a mass hierarchy in the scalar sector which is the inverse of the fermion mass hierarchy. We show in detail why $\Delta S=2\mathrm{}$ FCNCs are greatly suppressed when compared with naive estimates for nondegenerate squarks.