9,191 research outputs found
Diphoton decay for a GeV scalar boson in an model
In the context of a nonuniversal and anomaly free extension of the
standard model, we examine the decay of a GeV scalar singlet state,
, as a possible explanation of the observed diphoton excess
announced by the ATLAS and CMS collaborations at CERN-LHC collider. One-loop
decay to photons is allowed through three heavy singlet quarks and one charged
Higgs boson into the loop. We obtain, for different width approximations and
for masses of the exotic singlet quarks in the region GeV, a
production cross section compatible
with ATLAS and CMS collaborations data. We also include another scalar singlet,
, as a dark matter candidate that may couple with the 750 GeV scalar at
tree level with production cross sections in agreement with ATLAS and CMS.Comment: 5 figures, discussion extended, 2 new figure
Diphoton decay for a 750 GeV scalar boson in a model
We propose a new GUT model free from anomalies, with
a 750 GeV scalar candidate which can decay into two photons, compatible with
the recent diphoton signal reported by ATLAS and CMS collaborations. This model
gives masses to all fermions and may explain the 750GeV signal through one loop
decays to with charged vector and charged Higgs bosons, as well
as up- and electron-like exotic particles that arise naturally from the
condition of cancellation of anomalies of the group. We
obtain, for different width approximations, allowed mass regions from 900 GeV
to 3 TeV for the exotic up-like quark, in agreement with ATLAS and CMS
collaborations data.Comment: 4 figures, discussion extended, 1 new figur
Leptogenesis in the presence of exact flavor symmetries
In models with flavor symmetries in the leptonic sector leptogenesis can take
place in a very different way compared to the standard leptogenesis scenario.
We study the generation of a asymmetry in these kind of models in the
flavor symmetric phase pointing out that successful leptogenesis requires (i)
the right-handed neutrinos to lie in different representations of the flavor
group; (ii) the flavons to be lighter at least that one of the right-handed
neutrino representations. When these conditions are satisfied leptogenesis
proceeds due to new contributions to the CP violating asymmetry and -depending
on the specific model- in several stages. We demonstrate the validity of these
arguments by studying in detail the generation of the asymmetry in a
scenario of a concrete flavor model realization.Comment: 25 pages, 7 figures; version 2: A few clarifications added. Version
matches publication in JHE
Análisis de los suelos del piedemoente de la vertiente norte de la Sierra de Alhama (Granada, España)
[Resumen] El piedemonte que enlaza la sierra de Alhama y el poljé de Zafarraya puede considerarse como un glacis incipiente sobre el que desarrollan suelos cuya morfologÃa es heredada del material parental. Los suelos son mayoritariamente Gleysoles y Regosoles, con o sin carbonatos, arcillosos y de fuerte consistencia, motivo que asociado al relieve justifica el alto Ãndice de erosionabilidad y el que exijan un serio acondicionamiento para ser usado agricolamente. Dada la posición fisiográfica y la propia naturaleza edáfica, también se utiliza el terreno para almacenar agua de lluvia destinada a riego. En cuanto a la génesis, son suelos poco Desarrolla dos y el hecho evolutivo más significativo es la transformación de la arcilla heredada (ilita-interestratificados-esmectita).[Abstract] The footslope in between Alhama mountain rouge and Zafarraya polje could be considered as an incipient glacis which shows soil with an inherited morphology from the parent material developing over it. Soils are mainly Gleysols and Regosols, with or without carbonates, clayed and with a strong consistence; these characteristics asociated to relief are the justification of the high erodibility index and the excigence of a serious arranging to be farmerly used. With the fisiographic position and own edaphic nature given, even the land use could be in order to store rainfall water for irrigation. For genetical studies, these are low developed soils and the most significant thing in their evolution is the inherated clay transformation (illite-interstratified-smectite)
Beyond with the general 2HDM-III for
We review the parameter regions allowed by measurements of
and by a theoretical limit on in terms of generic scalar and pseudoscalar new physics
couplings, and . We then use these regions as constraints to predict
the ranges for additional observables in including the
differential decay distributions ; the ratios
and ; and the tau-lepton
polarisation in , with emphasis on the CP violating
normal polarisation. Finally we map the allowed regions in and into
the parameters of four versions of the Yukawa couplings of the general 2HDM-III
model. We find that the model is still viable but could be ruled out by a
confirmation of a large .Comment: 27 pages, 11 figures, major changes with new analysis and plot
Surfaces containing a family of plane curves not forming a fibration
We complete the classification of smooth surfaces swept out by a
1-dimensional family of plane curves that do not form a fibration. As a
consequence, we characterize manifolds swept out by a 1-dimensional family of
hypersurfaces that do not form a fibration.Comment: Author's post-print, final version published online in Collect. Mat
Scalar coupling limits and diphoton Higgs decay from LHC in an model with scalar dark matter
In the context of an nonuniversal extension of the standard model
free from anomalies, we introduce a complex scalar singlet candidate to be dark
matter. In addition, an extra scalar doublet and a heavy scalar singlet are
required to provide masses to all fermions and to break spontaneously the
symmetries. From unitarity and stability of the Higgs potential, we find the
full set of bounds and order relations for the scalar coupling constants. Using
recent data from the CERN-LHC collider, we study the signal strenght of the
diphoton Higgs decay , which imposes very stringent bounds
to the scalar couplings and other scalar parameters. We obtain constraints in
different scenarios of the space of parameters, where decays into dark matter
may or may not contribute according to the mass of the scalar dark matter
candidate. By assuming that the lightest scalar boson of the model corresponds
to the observed Higgs boson, we evaluate deviations from the SM of the
trilineal Higgs self-coupling. The conditions from unitarity, stability and
Higgs diphoton decay data allow trilineal deviations in the range .Comment: Additional figures and analysis in new versio
Numerical Study of the Intrinsic and Feedback Dynamics of a Gas-Solid Fluidized Bed
The aim of this paper is to understand the complex spatio-temporal patterning of the dense bed when the inlet conditions can be modified by the bed itself. In this study, the inlet conditions (fluid pressure and velocity upstream the bed) take into account resistive effects from the distributor and capacitive ones from the air-supply system (plenum). The present work addresses particularly the issue of the transition between multiple and single bubble regimes that occurs for some particular inlet conditions
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