37 research outputs found
Neutrino Mass Squared Differences in the Exact Solution of a 3-3-1 Gauge Model without Exotic Electric Charges
The mass splittings for the Majorana neutrinos in the exact solution of a
particular 3-3-1 gauge model are computed here in detail. Since both
and the mass splittings ratio
are taken into account, the analytical calculations
seem to predict an inverted mass hierarchy and a mixing matrix with a texture
based on a very close approximation to the bi-maximal mixing. The resulting
formulas for the mass squared differences can naturally accomodate the
available data if the unique free parameter () gets very small values
(). Consequently, the smallness of the parameter requires
(according to our method) a large breaking scale TeV
in the model. Hence, the results concerning the neutrino mass splittings may
lead to a more precise tuning in the exact solution of the 3-3-1 model of
interest, being able - at the same time - to recover all the Standard Model
phenomenology and predict the mass spectrum of the new gauge bosons
in accordance with the actual data. The minimal absolute mass
in the neutrino sector is also obtained - eV - in the case
of our suitable approximation for the bi-maxcimal mixing.Comment: 10 pages, no figure
The exact eigenstates of the neutrino mass matrix without CP-phase violation
In this paper we obtain the exact mass-eigenstates of the Majorana physical
neutrinos. We start by taking into account a general mass matrix
without any CP-phase violation. It is then diagonalized by exactly solving an
appropriate set of equations. The solution supplies straightforwardly the mass
eigenvalues depending on the diagonal entries and mixing angles. Finally, the
consequences of these analytical expressions are discussed assuming various
phenomenological restrictions such as conserving the global lepton number
and the interchange symmetry. The minimal
absolute mass in the neutrino sector is also obtained since the two plausible
scenarios invoked above are employed.Comment: 9 pages, no figure
Neutrino mixing matrix in the 3-3-1 model with heavy leptons and symmetry
We study the lepton sector in the model based on the local gauge group
which do not contain particles with
exotic electric charges. The seesaw mechanism and discrete symmetry are
introduced into the model to understand why neutrinos are especially light and
the observed pattern of neutrino mixing. The model provides a method for
obtaining the tri-bimaximal mixing matrix in the leading order. A non-zero
mixing angle presents in the modified mixing matrix.Comment: 10 page
Conserving the lepton number in the exact solution of a 3-3-1 gauge model with right-handed neutrinos
In this paper we consider a plausible scenario with conserved lepton number
\textbf{} within the framework of the exact solution
of a particular 3-3-1 gauge model. We discuss what are the consequences of
conserving this global leptonic symmetry from the viewpoint of the neutrino
mass matrix constructed via special Yukawa terms (involving tensor products
among Higgs triplets). We prove that the actual experimental data can naturally
be reproduced by our scenario since soft breaking terms with respect to this
lepton symmetry are properly introduced. As a consequence, our solution
predicts for the neutrino sector the correct mass splitting ratio (), the inverted mass hierarchy, the
correct values for the observed mixing angles (
and )and the absolute mass of the lightest neutrino
(eV)independent of the breakung scale of the model.Comment: 10 pages, no figure
New hominin remains and revised context from the earliest Homo erectus locality in East Turkana, Kenya
Large theta_13 from a model with broken L_e-L_mu-L_tau symmetry
Recent data in the neutrino sector point towards a relatively large value of
the reactor angle, incompatible with a vanishing theta_ 13 at about 3 sigma. In
order to explain such a result, we propose a SUSY model based on the broken
L_e-L_mu-L_tau symmetry, where large deviations from the symmetric limit
theta_12 = pi/4, tan(theta_23) \sim O(1) and theta_13 = 0 mainly come from the
charged lepton sector. We show that a description of all neutrino data is
possible if the charged lepton mass matrix has a special pattern of complex
matrix elements.Comment: 9 pages, 2 figures. v2: comments and references added, as published
in JHE
The seesaw mechanism at TeV scale in the 3-3-1 model with right-handed neutrinos
We implement the seesaw mechanism in the 3-3-1 model with right-handed
neutrinos. This is accomplished by the introduction of a scalar sextet into the
model and the spontaneous violation of the lepton number. We identify the
Majoron as a singlet under symmetry, which makes it
safe under the current bounds imposed by electroweak data. The main result of
this work is that the seesaw mechanism works already at TeV scale with the
outcome that the right-handed neutrino masses lie in the electroweak scale, in
the range from MeV to tens of GeV. This window provides a great opportunity to
test their appearance at current detectors, though when we contrast our results
with some previous analysis concerning detection sensitivity at LHC, we
conclude that further work is needed in order to validate this search.Comment: about 13 pages, no figure
KeV right-handed neutrinos from type II seesaw mechanism in a 3-3-1 model
We adapt the type II seesaw mechanism to the framework of the 3-3-1 model
with right-handed neutrinos. We emphasize that the mechanism is capable of
generating small masses for the left-handed and right-handed neutrinos and the
structure of the model allows that both masses arise from the same Yukawa
coupling. For typical values of the free parameters of the model we may obtain
at least one right-handed neutrino with mass in the KeV range. Right-handed
neutrino with mass in this range is a viable candidate for the warm component
of the dark matter existent in the universe.Comment: About 10 pages, no figure
Data for: A Late Maeotian age for the enigmatic “Pebbly Breccia” unit in DSDP Hole 380A of the Black Sea
Table.1 Calcareous nannofossils and diatoms from DSDP Hole 380A - Data Fil
Data for: A Late Maeotian age for the enigmatic “Pebbly Breccia” unit in DSDP Hole 380A of the Black Sea
Table.1 Calcareous nannofossils and diatoms from DSDP Hole 380A - Data FileTHIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV