Quark-lepton symmetry has been shown to be inconsistent with baryogenesis via
leptogenesis in natural schemes of the see-saw mechanism. Within the
phenomenological approach of textures, we relax this strict symmetry and
propose weaker conditions, namely models of the neutrino Dirac mass matrix
MDβ which have the same hierarchy as the matrix elements of Muβ. We call
this guide-line generalized hierarchical quark-lepton symmetry. We consider
in detail particular cases in which the moduli of the matrix elements of MDβ
are equal to those of Muβ. Within the phenomenological approach of textures,
we try for the heavy Majorana mass matrix diagonal and off-diagonal forms. We
find that an ansatz for MDβ preserving the hierarchy, together with an
off-diagonal model for the heavy Majorana neutrino mass, is consistent with
neutrino masses, neutrino mixing and baryogenesis via leptogenesis for an
intermediate mass scale mRββΌ1012 GeV. The preservation of the
hierarchical structure could come from a possible symmetry scheme.Comment: 12 pages, RevTex4. Title and abstract changed. Revised and enlarged
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