Updated Numerical Analysis of eV Seesaw with Four Generations

Abstract

We extend the so-called "eV seesaw" scenario, where M R is of eV order, to four lepton generations. The fourth generation gives a heavy pseudo-Dirac neutral lepton, which largely decouples from other generations and is relatively stable. The framework naturally gives 3 active and 3 sterile neutrinos. We update a previous numerical analysis of a 3+3 study of the LSND anomaly, taking into account recent results from the MiniBooNE experiment. In particular, we study the implications for the third mixing angle, as well as CP violation.