26 research outputs found
Base genética da resistência de trigo à brusone: avanços via estudos de QTLs.
Encouraged by the recent results from neutrino oscillation experiments, we
perform an analytical study of -inspired models and leptogenesis with
hierarchical right-handed (RH) neutrino spectrum. Under the approximation of
negligible misalignment between the neutrino Yukawa basis and the charged
lepton basis, we find an analytical expression for the final asymmetry directly
in terms of the low energy neutrino parameters that fully reproduces previous
numerical results. This expression also shows that is possible to identify an
effective leptogenesis phase for these models. When we also impose the wash-out
of a large pre-existing asymmetry , the strong thermal (ST)
condition, we derive analytically all those constraints on the low energy
neutrino parameters that characterise the {\rm ST}--inspired
leptogenesis solution, confirming previous numerical results. In particular we
show why, though neutrino masses have to be necessarily normally ordered, the
solution implies an analytical lower bound on the effective neutrino-less
double beta decay neutrino mass, , for , testable with next generation experiments. This, in
combination with an upper bound on the atmospheric mixing angle, necessarily in
the first octant, forces the lightest neutrino mass within a narrow range - (corresponding to -). We also show why the solution could correctly predict
a non-vanishing reactor neutrino mixing angle and requires the Dirac phase to
be in the fourth quadrant, implying (and ) negative as
hinted by current global analyses. Many of the analytical results presented
(expressions for the orthogonal matrix, RH neutrino mixing matrix, masses and
phases) can have applications beyond leptogenesis.Comment: 46 pages, 10 figures; v2: Ref.'s added, typos corrected; v3: added
fig. 10, matches version to appear in NP