arXiv:hep-ph/0307245·v2·High Energy Physics — Phenomenology
3+2 neutrinos in a see-saw variation
G. J. Stephenson · Jr.(1) · T. Goldman (2) · B. H. J. McKellar (3) · M. Garbutt (3) ((1) U. of New Mexico, (2) LANL, (3) U. of Melbourne)
Abstract
If the sterile neutrino mass matrix in an otherwise conventional see-saw model has a rank less than the number of flavors, it is possible to produce pseudo-Dirac neutrinos. For the rank 1 case, 3+2 scenarios devolve naturally, as we show by example. Additionally, we find that the lower rank see-saw suppresses some mass differences, so that small mass differences do not require that the individual masses of each neutrino must also be small.
Comments: 17pp., 1 fig., revtex4; typo corrected in Table