1,036 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
Charged lepton flavour violation from low scale seesaw neutrinos
In the work presented here, we have studied the impact of right handed
neutrinos, which are introduced to account for the evidence of neutrino masses,
on charged lepton flavour violating observables. In particular, we have focused
on the loop induced decays of the Z boson into two leptons of different
flavour. We have performed a numerical study of the rates predicted for these
processes within the Inverse Seesaw model, specifically considering scenarios
where transitions are suppressed. Our conclusion, after comparison
with the most relevant experimental constraints, is that branching ratios as
large as can be predicted in the or
channels, together with heavy neutrinos having masses of the TeV order. Such
rates could be accessible at next generation colliders.Comment: 13 pages, 5 figures, 3 tables. Proceedings of the Corfu Summer
Institute 2016 "School and Workshops on Elementary Particle Physics and
Gravity", 31 August - 23 September 2016, Corfu, Greec
A first checklist of the lichen-forming fungi of the Venezuelan Andes
Basing on an evaluation of the literature and some unpublished collections, 745 taxa of lichen forming-fungi are reported from the Venezuelan Andes, including 10 infraspecific taxa. Of these taxa 37 are new records for Venezuela: Actinoplaca vulgaris (Müll. Arg.) Vezda & Poelt, Asterothyrium decipiens (Rehm) R. Sant., Calopadia foliicola (Fée) Vezda, C. fusca (Müll. Arg.) Vezda, C. phyllogena (Müll. Arg.) Vezda, Chrysothrix chlorina (Ach.) J. R. Laundon, Cystocoleus ebeneus (Dillwyn) Thwaites, Diploschistes scruposus (Schreb.) Norm., Echinoplacaleucotrichoides (Vain.) R. Sant., Fellhanerabouteillei (Desm.) Vezda, F.dominicana (Vain.) Vezda, F. fuscatula (Müll. Arg.) Vezda, F. sublecanorina (Nyl.) Vezda, Gyalectidium filicinum Müll. Arg., Lecidea limosa Ach., Lepraria neglecta Auct., Ochrolechia africana Vain., Peltigera vainioi Gyelnik, Phyllobathelium nigrum R. Sant. & Tibell, Phyllophialealba R. Sant., Polymeridiumalbidum (Müll. Arg.) R. C. Harris, Porina epiphylla (Fée) Fée, Racodium rupestre Pers., Ramalina asahinae W. Culb. & C. Culb., R. calcarata Krog & Swinsc., R. puiggarii Müll Arg., R. rectangularis Nyl., Rhizoplaca melanophthalma (DC.) Leuckert & Poelt, Strigula antillarum (Fée) Müll. Arg., S. platypoda (Müll. Arg.) R. C. Harris, Tapellaria epiphylla (Müll. Arg.) R. Sant., T.nana (Fée) R. Sant., Tephromela aglaea (Sommerf.) Hertel & Rambold, Tricharia vainioi R. Sant., Trichothelium epiphyllum Müll. Arg., T. bipindense F. Schill. and Vezdaea foliicola Sérusiaux. Another 4 species are new records only for the Venezuelan Andes: Dimerellaepiphylla (Müll. Arg.) Malme, Porinaatrocoerulea Müll. Arg., Ramalina peruviana Ach. and Woessia apiahica (Müll. Arg.) Sérus. A list of synonyms used in the consulted literature is added. Four new combinations are proposed: Dictyonema zahlbruckneri (Schiffn.) V. Marcano, Heterodermia tropica (Kurok.) Sipman, Parmelinopsis cleefii (Sipman) V. Marcano & Sipman and Phyllobaeislinearis (De Vries) V. Marcano & Sipman
Radiative corrections to from three generations of Majorana neutrinos and sneutrinos
In this work we study the radiative corrections to the mass of the lightest
Higgs boson of the MSSM from three generations of Majorana neutrinos and
sneutrinos. The spectrum of the MSSM is augmented by three right handed
neutrinos and their supersymmetric partners. A seesaw mechanism of type I is
used to generate the physical neutrino masses and oscillations that we require
to be in agreement with present neutrino data. We present a full one-loop
computation of these Higgs mass corrections, and analyze in full detail their
numerical size in terms of both the MSSM and the new (s)neutrino parameters. A
critical discussion on the different possible renormalization schemes and their
implications is included.Comment: 42 pages, 39 figures, 1 appendix, version published in AHE
Utilisation de modèles linéaires généralisés pour évaluer les stratégies de pêche thonière à la senne en présence d'espèces associées dans l'Atlantique ouest
Les stratégies de pêche, développées par les capitaines des thoniers senneurs vénézuéliens dans la mer des Caraïbes, reposent sur la recherche d'indices visuels indiquant la présence de thons à la surface de l'océan. Une fois que la détection est réalisée, le senneur peut choisir la tactique qui consiste à demander l'aide d'un thonier canneur (pêche à l'appât vivant) afin d'augmenter le taux de réussite d'un coup de senne. Pour prendre en compte la variabilité de différents facteurs, comme la saison, les indices de détection associés aux bancs, l'aide du thonier canneur, les espèces de thons et le poids moyen des poissons présents dans le banc, les probabilités de réalisation de certains événements sont estimées à l'aide de la modélisation Logit, issue de modèles Log-linéaires. Les probabilités de capturer des bancs de gros individus sont maximales lorsque l'albacore est l'espèce dominante et que la pêche a lieu sur banc libre ou sur requin-baleine ; cet effet est d'autant plus marqué en saison sèche. En revanche, si le listao est l'espèce dominante, la probabilité de capturer des gros individus est faible, en particulier lorsque la pêche est réalisée sur des baleines. Les résultats de cette modélisation sont intégrés dans un arbre de décision. Si on retient le critère de l'espérance mathématique des gains potentiels, l'aide du thonier canneur ne semble pas être la meilleure des tactiques possibles. Pourtant son impact est positif sur le taux de réussite d'un coup de senne, puisque le pourcentage de calées positives passe de 58% sans aide à 85% avec aide. L'efficacité de cette aide dépend du type d'association rencontré. Elle augmente lorsqu'il s'agit de bancs libres ou en association avec des baleines, mais diminue lorsque le banc est associé à un requin-baleine... (D'après résumé d'auteur
3D CFD Modeling Investigation of Potential Vortex Formation at the Intakes of Caruachi Powerhouse
In this paper, the 3-D CFD simulation of the free-surface flow approaching the
intakes of Caruachi Powerhouse is presented. The aim of the investigation is to determine
whether or not vortex structures are likely to appear from the water surface through the intakes, as the result of the presence of cofferdams placed few meters upstream of the intakes. The presence of cofferdams was a note of concern with regard to the effects they might have on the turbine intakes once the hydroelectric central starts operating. In all the considered conditions, results did not show neither strong surface vortices in the proximities of the Power House intakes, nor air entrainment-entrapment towards the intakes, which reflects the safe operation of the turbines in the presence of the cofferdams. The latter added in decision taking on leaving the cofferdams submerged instead of removing them, which resulted in cost savings for the projec
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