Supersymmetry inspired minimal lepton number violation - art. no. 015014

A minimal lepton number violation (LNV) is proposed which could naturally a ppear in SUSY theories, if Yukawa and LNV couplings had a common origin. Ac cording to this idea properly implemented into the minimal supersymmetric s tandard model (MSSM) with an additional Abelian flavor symmetry, a prototyp e LNV appears due to the mixing of leptons with superheavy Higgs doublet me diating Yukawa couplings. As a result, all significant physical manifestati ons of LNV reduce to those of the effective trilinear couplings LL (E) over bar and LQ (D) over bar aligned, by size and orientation ina flavor space, with the down fermion (charged lepton and down quark) effective Yukawa cou plings, while the effective bilinear terms appear generically suppressed re lative to an ordinary mu term of the MSSM. The detailed phenomenology of th e model related to the flavor-changing processes both in quark and lepton s ectors, radiatively induced neutrino masses, and decays of the LSP, is pres ented. Remarkably, the model can straightforwardly be extended to a grand u nified framework and an explicit example with an SU(7) GUT is thoroughly di scussed.