133 research outputs found
Triple seesaw mechanism
On fitting the type II seesaw mechanism into the type I seesaw mechanism, we
obtain a formula to the neutrino masses which get suppressed by high-scale
in its denominator. As a result, light neutrinos are naturally obtained
with new physics at TeV scale. As interesting consequence, the mechanism may be
directly probed at the LHC by directly producing the TeV states intrinsic of
the mechanism. We show that the 3-3-1 model with right-handed neutrinos
realizes naturally such seesaw mechanism.Comment: About 13 pages, no figure
O mercado de crédito de carbono e as possibilidades da obtenção de biodiesel a partir de óleos vegetais.
bitstream/item/108088/1/2009-DOC-0104.pd
Explaining ATLAS and CMS Results Within the Reduced Minimal 3-3-1 model
Recently the ATLAS and CMS collaborations announced the discovery of a higgs
particle with a mass of GeV. The results are mildly consistent with
the Standard Model Higgs boson. However, the combined data from these
collaborations seem to point to an excess in the
channel. In this work we analyze under which conditions this excess may be
plausibly explained within the reduced minimal 3-3-1 model, while being
consistent with bb, WW, ZZ and channels. Moreover, we derive the
properties of the heavy neutral and the doubly charged scalars predicted by the
model. We then conclude that at a scale of a few TeV, this model provides a
good fit to the ATLAS and CMS signal strength measurements, and therefore
stands as an appealing alternative to the standard model.Comment: 23 pages, 9 figures. References adde
Combining type I and type II seesaw mechanisms in the minimal 3-3-1 model
The minimal 3-3-1 model is perturbative until energies around 4-5TeV, posing
a challenge to generate neutrino masses at eV scale, mainly if one aims to take
advantage of the seesaw mechanism. As a means to circumvent this problem we
propose a modification of the model such that it accommodates the type I and
type II seesaw mechanisms altogether. We show that the conjunction of both
mechanisms yield a neutrino mass expression suppressed by a high power of the
cutoff scale, , in its denominator. With such a suppression term we
naturally obtain neutrino masses at eV scale when is around few TeV. We
also investigate the size of lepton flavor violation through the process .Comment: about 15 pages, no figure
Novel sources of Flavor Changed Neutral Currents in the model
Sources of Flavor Changed Neutral Currents (FCNC) naturally emerge from a
well motivated framework called 3-3-1 with right-handed neutrinos model,
for short, mediated by an extra neutral gauge boson .
Following previous works we calculate these sources and in addition we derive
new ones coming from CP-even and -odd neutral scalars which appear due to their
non-diagonal interactions with the physical standard quarks. Furthermore we
show that bounds related to the neutral mesons systems and may be significantly strengthened in the presence of these new
interactions allowing us to infer stronger constraints on the parameter space
of the model.Comment: Published version. 10 pages, 6 figure
Deep learnig analysis of the inverse seesaw in a 3-3-1 model at the LHC
Inverse seesaw is a genuine TeV scale seesaw mechanism. In it active
neutrinos with masses at eV scale requires lepton number be explicitly violated
at keV scale and the existence of new physics, in the form of heavy neutrinos,
at TeV scale. Therefore it is a phenomenologically viable seesaw mechanism
since its signature may be probed at the LHC. Moreover it is successfully
embedded into gauge extensions of the standard model as the 3-3-1 model with
the right-handed neutrinos. In this work we revisit the implementation of this
mechanism into the 3-3-1 model and employ deep learning analysis to probe such
setting at the LHC and, as main result, we have that if its signature is not
detected in the next LHC running with energy of 14 TeVs, then, the vector boson
of the 3-3-1 model must be heavier than 4 TeVs
Fermion family number and the Z-Z mixing in the 3-3-1 model with right-handed neutrinos
Theoretical consistency of the 3-3-1 model with right-handed neutrinos
demands that the number of family of fermions be exactly equal to three. In
this brief report we show that such theoretical requirement results in a clean
and severe bound on the Z-Z mixing angle: -3,979\times
10^{-3}<\phi<1,309\times 10^{-4} {with 90% CL}.Comment: Minor modification in the conclusions, some refs added, to appear at
MPL
No gaussianidad y correcciones de lazo en un modelo inflacionario de rodadura lenta con potencial escalar cuadrático de dos componentes. Parte II
We calculate the trispectrum Tζ(k1, k2, k3, k4) of the curvature perturbation ζ, generated during an inflationary slow-roll epoch and considering a two-component quadratic scalar potential. At calculating we consider tree-level and one-loop contributions, showing that it is possible to obtain an observable value for the non-gaussianity level Ï„NL if Tζ is dominated by the one-loop contribution. The work is developed taking into account that there exist some physical restrictions that reduce the available parameter window. Such conditions are: the existence of a coupling constant that guarantees making the calculation in a perturbative regime, the relative weight of the tree-level and one-loop contributions, the spectrum normalisation, the observed spectral index, and the minimum amount of inflation required to solve the horizon problem.Se calcula el triespectro Tζ(k1,k2,k3,k4) de la perturbación en la curvatura ζ, generado durante una época inflacionaria de rodadura lenta y considerando un potencial escalar cuadrático de dos componentes. En el cálculo se consideran contribuciones a nivel árbol y a un lazo, y se muestra que es posible obtener un valor observable para el nivel de no gaussianidad Ï„NL si Tζ es dominado por la contribución a un lazo. El trabajo se desarrolla teniendo en cuenta que existen algunas restricciones fÃsicas que reducen la ventana de parámetros disponible. Estas condiciones son: la existencia de una constante de acoplamiento que garantiza la realización del cálculo en un régimen perturbativo, el peso relativo de las contribuciones a nivel árbol y a un lazo, la normalización del espectro, el Ãndice espectral observado y el monto de inflación mÃnimo necesario para resolver el problema de horizonte
No gaussianidad y correcciones de lazo en un modelo inflacionario de rodadura lenta con potencial escalar cuadrático de dos componentes. Parte II
Se calcula el triespectro Tζ(k1,k2,k3,k4) de la perturbación en la curvatura ζ, generado durante una época inflacionaria de rodadura lenta y considerando un potencial escalar cuadrático de dos componentes. En el cálculo se consideran contribuciones a nivel árbol y a un lazo, y se muestra que es posible obtener un valor observable para el nivel de no gaussianidad τNL si Tζ es dominado por la contribución a un lazo. El trabajo se desarrolla teniendo en cuenta que existen algunas restricciones fÃsicas que reducen la ventana de parámetros disponible. Estas condiciones son: la existencia de una constante de acoplamiento que garantiza la realización del cálculo en un régimen perturbativo, el peso relativo de las contribuciones a nivel árbol y a un lazo, la normalización del espectro, el Ãndice espectral observado y el monto de inflación mÃnimo necesario para resolver el problema de horizonte
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