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, $H \to l_k\bar l_m$, 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($H \to l_k\bar l_m$) rates for the three possible channels, $l_k\bar l_m=\mu \bar \tau,\, e \bar \tau,\, e \bar \mu$, 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, $l_m \to l_k \gamma$, within this same ISS context, and require full compatibility of our predictions with the present experimental bounds for the three radiative decays, $\mu \to e \gamma$, $\tau \to \mu \gamma$, and $\tau \to e \gamma$. 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 μτjj\mu\tau j j 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 ${\cal O}(1)$ 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 $\mu\tau jj$ 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 $\mu -e$ transitions are suppressed. Our conclusion, after comparison with the most relevant experimental constraints, is that branching ratios as large as $10^{-7}$ can be predicted in the $\tau -\mu$ or $\tau -e$ 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

Radiative corrections to MhM_h 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

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

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