962 research outputs found
Anomalous Higgs Couplings
We review the effects of new effective interactions on the Higgs boson
phenomenology. New physics in the electroweak bosonic sector is expected to
induce additional interactions between the Higgs doublet field and the
electroweak gauge bosons leading to anomalous Higgs couplings as well as to
anomalous gauge-boson self-interactions. Using a linearly realized invariant effective Lagrangian to describe the bosonic sector of
the Standard Model, we review the effects of the new effective interactions on
the Higgs boson production rates and decay modes. We summarize the results from
searches for the new Higgs signatures induced by the anomalous interactions in
order to constrain the scale of new physics in particular at CERN LEP and
Fermilab Te vatron colliders.Comment: 35 pages, latex using epsfig.sty psfig.sty and axodraw.sty, 16
postscript figure
Spontaneous R-Parity violation bounds
We investigate bounds from tree-level and one-loop processes in generic
supersymmetric models with spontaneous R-parity breaking in the superpotential.
We analyse the bounds from a general point of view. The bounds are applicable
both for all models with spontaneous R-parity violation and for explicit
bilinear R-parity violation based on general lepton-chargino and
neutrino-neutralino mixings. We find constraints from semileptonic B, D and K
decays, leptonic decays of the mu and tau, electric dipole moments, as well as
bounds for the anomalous magnetic moment of the muon.Comment: 22 page
Probing neutrino properties with charged scalar lepton decays
Supersymmetry with bilinear R-parity violation provides a predictive
framework for neutrino masses and mixings in agreement with current neutrino
oscillation data. The model leads to striking signals at future colliders
through the R-parity violating decays of the lightest supersymmetric particle.
Here we study charged scalar lepton decays and demonstrate that if the scalar
tau is the LSP (i) it will decay within the detector, despite the smallness of
the neutrino masses, (ii) the relative ratio of branching ratios Br({tilde
tau}_1 --> e sum nu_i)/ Br({tilde tau}_1 --> mu sum nu_i) is predicted from the
measured solar neutrino angle, and (iii) scalar muon and scalar electron decays
will allow to test the consistency of the model. Thus, bilinear R-parity
breaking SUSY will be testable at future colliders also in the case where the
LSP is not the neutralino.Comment: 24 pages, 8 ps figs Report-no.: IFIC/02-33 and ZU-TH 11/0
Neutrino Masses and Mixings from Supersymmetry with Bilinear R--Parity Violation: A Theory for Solar and Atmospheric Neutrino Oscillations
The simplest unified extension of the MSSM with bi-linear R--Parity violation
naturally predicts a hierarchical neutrino mass spectrum, in which one neutrino
acquires mass by mixing with neutralinos, while the other two get mass
radiatively. We have performed a full one-loop calculation of the
neutralino-neutrino mass matrix in the bi-linear \rp MSSM, taking special care
to achieve a manifestly gauge invariant calculation. Moreover we have performed
the renormalization of the heaviest neutrino, needed in order to get meaningful
results. The atmospheric mass scale and maximal mixing angle arise from
tree-level physics, while solar neutrino scale and oscillations follow from
calculable one-loop corrections. If universal supergravity assumptions are made
on the soft-supersymmetry breaking terms then the atmospheric scale is
calculable as a function of a single \rp violating parameter by the
renormalization group evolution due to the non-zero bottom quark Yukawa
coupling. The solar neutrino problem must be accounted for by the small mixing
angle (SMA) MSW solution. If these assumptions are relaxed then one can
implement large mixing angle solutions, either MSW or just-so. The theory
predicts the lightest supersymmetic particle (LSP) decay to be observable at
high-energy colliders, despite the smallness of neutrino masses indicated by
experiment. This provides an independent way to test this solution of the
atmospheric and solar neutrino anomalies.Comment: 46 pages, references added + several misprints correcte
Broken R-parity, stop decays, and neutrino physics
We discuss the phenomenology of the lightest stop in models where R-parity is
broken by bilinear superpotential terms. In this class of models we consider
scenarios where the R-parity breaking two-body decay ~t_1->\tau^+b competes
with the leading three-body decays such as ~t_1->W^+b~\chi^0_1. We demonstrate
that the R-parity violating decay can be sizable and in some parts of the
parameter space even the dominant one. Moreover we discuss the expectations for
\~t_1->\mu^+b and ~t_1->e^+b. The recent results from solar and atmospheric
neutrinos suggest that these are as important as the tau bottom mode. The
\~t_1->l^+b decays are of particular interest for hadron colliders, as they may
allow a full mass reconstruction of the lighter stop. Moreover these decay
modes allow cross checks on the neutrino mixing angle involved in the solar
neutrino puzzle complementary to those possible using neutralino decays. For
the so--called small mixing angle or SMA solution ~t_1->e^+b should be
negligible, while for the large mixing angle type solutions all ~t_1->l^+b
decays should have comparable magnitude.Comment: 51 pages, 6 figures, LaTeX2e and RevTeX4, published versio
Evaluation of the Predictive Ability, Environmental Regulation and Pharmacogenetics Utility of a BMI-Predisposing Genetic Risk Score during Childhood and Puberty
The authors would like to thank the Spanish children and parents who participated in
the study.Polygenetic risk scores (pGRSs) consisting of adult body mass index (BMI) genetic
variants have been widely associated with obesity in children populations. The implication of
such obesity pGRSs in the development of cardio-metabolic alterations during childhood as well
as their utility for the clinical prediction of pubertal obesity outcomes has been barely investigated
otherwise. In the present study, we evaluated the utility of an adult BMI predisposing pGRS for the
prediction and pharmacological management of obesity in Spanish children, further investigating
its implication in the appearance of cardio-metabolic alterations. For that purpose, we counted
on genetics data from three well-characterized children populations (composed of 574, 96 and 124
individuals), following both cross-sectional and longitudinal designs, expanding childhood and
puberty. As a result, we demonstrated that the pGRS is strongly associated with childhood BMI
Z-Score (B = 1.56, SE = 0.27 and p-value = 1.90 × 10−8
), and that could be used as a good predictor of
obesity longitudinal trajectories during puberty. On the other hand, we showed that the pGRS is not
associated with cardio-metabolic comorbidities in children and that certain environmental factors
interact with the genetic predisposition to the disease. Finally, according to the results derived from a
weight-reduction metformin intervention in children with obesity, we discarded the utility of the
pGRS as a pharmacogenetics marker of metformin response.Plan Nacional de Investigacion Cientifica, Desarrollo e Innovacion Tecnologica (I + D + I), Instituto de Salud Carlos III-Health Research Funding (FONDOS FEDER)
PI1102042
PI1102059
PI1601301
PI1600871Spanish Ministry of Health, Social and Equality, General Department for Pharmacy and Health Products
EC10-243
EC10-056
EC10-281
EC10-227Regional Government of Andalusia ("Plan Andaluz de investigacion, desarrollo e innovacion (2018)")
P18-RT-2248Mapfre Foundation ("Research grants by Ignacio H. de Larramendi 2017")Instituto de Salud Carlos III
IFI17/0004
Some Implications of a Supersymmetric Model with R-Parity Breaking Bilinear Interactions
We investigate a supersymmetric scenario where R-parity is explicitly broken
through a term bilinear in the lepton and Higgs superfields in the
superpotential. We show that keeping such a term alone can lead to trilinear
interactions, similar to those that are parametrized by -and
in the literature, involving the physical fields. The upper limits
of such interactions are predictable from the constraints on the parameter
space imposed by the lepton masses and the neutrino mass limits. It is observed
that thus the resulting trilinear interactions are restricted to values that
are smaller than the existing bounds on most of the -and
-parameters. Some phenomenological consequences of such a scenario
are discussed.Comment: 26 Pages, 6 Postscript figures, Latex. An additional set of
references has been included. Typographic corrections have been made. Figures
remain all unchanged. An additional typographic correction has been mad
Search for Non-standard Higgs Boson in Diphoton Events at p pbar Collisions
We estimate the attainable limits on the coupling of a non-standard Higgs
boson to two photons taking into account the data collected by the Fermilab
collaborations on diphoton events. We based our analysis on a general set of
dimension--6 effective operators that give rise to anomalous couplings in the
bosonic sector of the Standard Model. If the coefficients of all ``blind''
operators are of the same order of magnitude, bounds on the anomalous triple
vector-boson couplings can also be obtained.Comment: ReVTeX, 3 figure
Testing neutrino mixing at future collider experiments
Low energy supersymmetry with bilinear breaking of R-parity leads to a
weak-scale seesaw mechanism for the atmospheric neutrino scale and a radiative
mechanism for the solar neutrino scale. The model has striking implications for
collider searches of supersymmetric particles. Assuming that the lightest SUSY
particle is the lightest neutralino we demonstrate that (i) The neutralino
decays inside the detector even for tiny neutrino masses. (ii) Measurements of
the neutrino mixing angles lead to predictions for the ratios of various
neutralino branching ratios implying an independent test of neutrino physics at
future colliders, such as the Large Hadron Collider or a Linear Collider.Comment: LaTex, 35 pages, 20 figures included, version 2, section on model
shortened, Fig. 13 replaced, typos corrected, version to appear in Phys.Rev.
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