Chiral Extensions of the MSSM
  We present a class of extensions of the MSSM characterized by a fully chiral field content (no mu-terms) and no baryon or lepton number violating term in the superpotential due to an extra U'(1) gauge symmetry. The minimal model consist of the usual matter sector with family dependent U'(1) charges, six Higgs weak doublets, and three singlets required to give masses to the Higgsinos and cancel anomalies. We discuss its main features such as the tree level mass spectrum and the constraints on flavor changing processes. 
Gabriele Ferretti and Denis Karateev
hep-ph hep-th