Low-scale standard supersymmetric leptogenesis

Abstract

Strictly adhering to the standard supersymmetric seesaw mechanism, we present a neutrino mass model which allows successful standard thermal leptogenesis compatible with gravitino cosmology. At least some of the neutrino Yukawa couplings must be much larger than the naive estimates following from the seesaw formula. This leads to large BR(mu->e gamma), detectable in the next round of experiments. Ratios of mu->e gamma, tau->e gamma and tau->mu gamma branching ratios are predicted in terms of the measurable neutrino mass matrix.

Comments: 15 pages, 4 eps figures; v2: typos corrected, references added, reasoning clarified; v3: 16 pages, off-shell wash-out effects included in the addendum (pp.15-16)