815 research outputs found
Imprints of massive inverse seesaw model neutrinos in lepton flavor violating Higgs boson decays
In this paper we consider a Higgs boson with mass and other properties
compatible with those of the recently discovered Higgs particle at the LHC, and
explore the possibility of new Higgs leptonic decays, beyond the standard
model, with the singular feature of being lepton flavor violating (LFV). We
study these LFV Higgs decays, , within the context of the
inverse seesaw model (ISS) and consider the most generic case where three
additional pairs of massive right-handed singlet neutrinos are added to the
standard model particle content. We require in addition that the input
parameters of this ISS model are compatible with the present neutrino data and
other constraints, like perturbativity of the neutrino Yukawa couplings. We
present a full one-loop computation of the BR() rates for
the three possible channels, , and analyze in full detail the predictions as functions of the
various relevant ISS parameters. We study in parallel the correlated one-loop
predictions for the radiative decays, , within this same
ISS context, and require full compatibility of our predictions with the present
experimental bounds for the three radiative decays, , , and . After exploring the ISS parameter
space we conclude on the maximum allowed LFV Higgs decay rates within the ISS.Comment: 29 pages, 13 figures, 1 table, 1 appendix: v4 matches the manuscript
published in PR
Exotic events from heavy ISS neutrinos at the LHC
In this letter we study new relevant phenomenological consequences of the
right-handed heavy neutrinos with masses at the TeV energy scale,
working within the context of the Inverse Seesaw Model that includes three
pairs of quasi-degenerate pseudo-Dirac heavy neutrinos. We propose a new exotic
signal of these heavy neutrinos at the CERN Large Hadron Collider containing a
muon, a tau lepton, and two jets in the final state, which is based on the
interesting fact that this model can incorporate large Lepton Flavor Violation
for specific choices of the relevant parameters, particularly, the neutrino
Yukawa couplings. We will show here that an observable number of
exotic events, without missing energy, can be produced at this ongoing run of
the LHC.Comment: 7 pages, 4 figures. This version v3 matches the manuscript published
in Physics Letters
Explanatory Note to the Proposal for the Establishment of a Cooperative Programme for Field Bean Research in Latin America and the Caribbean Zone
Personal note by Luis Marcano on the background of the proposed Cooperative Program for Field Bean Research in Latin America, participation of member countries, the selection of IICA as its secretariat, and the presence of strong international, regional, and national institutes that will serve the program. Agenda item presented at TAC Seventh Meeting, February 1974
Still Free, Still Alive: Images of Haitian Collective Values Portrayed Through Child Characters in Lamartine’s Toussaint Louverture and Agnant’s Alexis d’Haïti
In this paper, I argue that the fundamental Haitian values of the struggle for freedom and the prevailing desire for independence are portrayed through the morals and personality of two child characters found in texts set in Saint-Domingue/Haiti. The first character is a young girl named Adrienne in Alphonse de Lamartine’s play Toussaint Louverture (1850) and the second is a young boy named Alexis in Marie-Célie Agnant’s novel Alexis d’Haiti (1999). Through these two characters, Lamartine and Agnant depict Haiti’s struggle to achieve freedom and to retain its unique cultural identity that has allowed this nation once called the “pearl of the Caribbean” to survive. [Page 132-33
A cluster model with random anisotropy for hysteresis jumps in CeNiCu alloys
Some Cerium compounds exhibit hysteresis cycles with sharp macroscopic jumps
in the magnetization at very low temperatures. This effect is attributed to the
formation of clusters in which the anisotropy competes with the applied
magnetic field. Here, we present a simple model where a lattice of
ferromagnetically coupled spins is separated in clusters of random sizes and
with random anisotropy. Within this model, we obtain hysteresis cycles
presenting jumps that behave in a similar way that the experimental ones, and
that disappear when increasing the temperature. The results are in good
agreement with the hysteresis cycles measured at very low temperatures in
CeNiCu and the comparison with these experimental results allows
to discriminate the relative importance of the mechanisms driving the thermal
evolution of the cycles.Comment: Accepted in PR
Collider phenomenology of vector resonances in WZ scattering processes
We study the production of vector resonances at the LHC via scattering
processes and explore the sensitivities to these resonances for the expected
future LHC luminosities. The electroweak chiral Lagrangian and the Inverse
Amplitude Method (IAM) are used for analyzing a dynamically generated vector
resonance, whose origin would be the (hypothetically strong) self interactions
of the longitudinal gauge bosons, and . We implement the unitarized
scattering amplitudes into a single model, the IAM-MC, that has been adapted to
MadGraph~5. It is written in terms of the electroweak chiral Lagrangian and an
additional effective Proca Lagrangian for the vector resonances, so that it
reproduces the resonant behavior of the IAM and allows us to perform a
realistic study of signal versus background at the LHC. We focus on the channel, discussing first on the potential of the hadronic and
semileptonic channels of the final , and next exploring in more detail the
clearest signals. These are provided by the leptonic decays of the gauge
bosons, leading to a final state with , ,
having a very distinctive signature, and showing clearly the emergence of the
resonances with masses in the range of -, which we have
explored.Comment: 8 pages, 5 figures, contributed to the XIII Quark Confinement and the
Hadron Spectrum - Confinement2018, 31 July - 6 August 2018, Maynooth
University, Irelan
Production of vector resonances at the LHC via WZ-scattering: a unitarized EChL analysis
In the present work we study the production of vector resonances at the LHC
by means of the vector boson scattering and explore the
sensitivities to these resonances for the expected future LHC luminosities. We
are assuming that these vector resonances are generated dynamically from the
self interactions of the longitudinal gauge bosons, and , and work
under the framework of the electroweak chiral Lagrangian to describe in a model
independent way the supposedly strong dynamics of these modes. The properties
of the vector resonances, mass, width and couplings to the and gauge
bosons are derived from the inverse amplitude method approach. We implement all
these features into a single model, the IAM-MC, adapted for MonteCarlo, built
in a Lagrangian language in terms of the electroweak chiral Lagrangian and a
chiral Lagrangian for the vector resonances, which mimics the resonant behavior
of the IAM and provides unitary amplitudes. The model has been implemented in
MadGraph, allowing us to perform a realistic study of the signal versus
background events at the LHC. In particular, we have focused our study on the
type of events, discussing first on the potential of the hadronic
and semileptonic channels of the final , and next exploring in more detail
the clearest signals. These are provided by the leptonic decays of the gauge
bosons, leading to a final state with ,
, having a very distinctive signature, and showing clearly the
emergence of the resonances with masses in the range of 1.5-2.5 TeV, which we
have explored.Comment: Revised version accepted for publication in JHEP. Enlarged analysis.
References added. 44 pages, 23 figures, 3 table
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