Effects of the neutrino B-term on the Higgs mass parameters and electroweak symmetry breaking

To embed the seesaw mechanism in the MSSM, two or three right-handed neutrino supermultiplets, Ni, have to be added to the model. In the presence of these new superfields, the soft supersymmetry breaking potential includes a lepton number violating mass term which is known as the neutrino B-term, MBνNN/2. In this paper, we study the effects of Bν on the Higgs mass parameters. Using the condition for the electroweak symmetry breaking, we derive an upper bound on Bν which, for some range of parameters, is two orders of magnitude stronger than the previous bounds. We also propose a simple model in which it is natural to have large values of Bν while the rest of the supersymmetry breaking terms are at the TeV scale or smaller.