Evading the Few TeV Perturbative Limit in 3-3-1 Models

Some versions of the electroweak SU(3)_L\otimesU(1)_X models cannot be treated within perturbation theory at energies of few TeV. An extended version for these models is proposed which is perturbative even at TeV scale posing no threatening inconsistency for test at future colliders. The extension presented here needs the addition of three octets of vector leptons, which leave three new leptonic isotriplets in the SU(2)_L\otimesU(1)_Y subgroup. With this representation content the running of the electroweak mixing angle, $\theta_W (\mu)$, is such that $\sin^2\theta_W(\mu)$ decreases with the increase of the energy scale $\mu$, when only the light states of the Standard Model group are considered. The neutral exotic gauge boson $Z^\prime$ marks then a new symmetry frontier.Comment: 15 pages, 2 figures, minor correction

A certificação das embalagens de madeira: importante avanço na importação e exportação de produtos e na segurança biológica.

bitstream/CENARGEN/30150/1/cultivar050207.pdfPublicado em 05/02/2007. Disponível em: Cultivar, cultivar050207; Abrafit, abrafitnr9807; Agrosoft, agrosoft050207; Pets, pets050207; ClicNews, clicnews050207; Ruralnet, ruralnet050207; Hotel Virtual, hvirtual050207; Boletim Pecuário, bpecuario050207; Zoonews, zoonews050207; D.O. Municípios Ceará, domceara050207

Bounds on the Simplest Little Higgs Model Mass Spectrum Through Z Leptonic Decay

We derive the leptonic neutral current in the simplest little Higgs model and compute the contribution of the model to the decay width $Z \to e^+e^-$. Using the precision electroweak data we obtain a strong lower bound $f\geq 5.6$ TeV at 95% C.L. on the characteristic energy scale of the model. It results in a lower bound for the new gauge bosons $W^{\prime\pm}$ and $Z^{\prime}$ as being $M_{W^{\prime\pm}}\geq 2.6$ TeV and $M_{Z^{\prime}}\geq 3.1$ TeV, respectively. We also present the allowed values of the $k=f_1/f_2$ which is the parameter relating the two vacuum expectation values of the scalar triplets in the model, and the $\mu$ parameter of a quadratic term, involving the triplets, necessary to provide an acceptable mass range for the standard Higgs boson.Comment: New references added, 13 pages. Version to be publishe

Plantas do futuro no presente [2].

bitstream/CENARGEN/30151/1/odisseu310507.pdfPublicado em 30/01/2007. Disponível em: Boletim Pecuário, boletimpecuario300107; ClicNews, clicnews300107; Hotel Virtual, hotelvirtual300107; Cultivar, cultivar280107; Página Rural, pgrural300107; Portal Agronegócio, pagronegocio310107; Criar e Plantar, criareplantar300107; Zoonews, zoonews020207; Pets, pets300107; Agrosoft, agrosoft300107; Ruralnet, ruralnet300107; Gazeta do Oeste, gazetadooeste020207

O uso do etanol como combustível no Brasil vai completar um século.

bitstream/item/78697/1/Campo-Grande-News-Versao-de-impressao.pd

The Left-Right SU(3)(L)xSU(3)(R)xU(1)(X) Model with Light, keV and Heavy Neutrinos

We construct a full left-right model for the electroweak interactions based on the $SU(3)_{L}\otimes SU(3)_{R}\otimes U(1)_{X}$ gauge symmetry. The fermion content of the model is such that anomaly cancellation restricts the number of families to be a multiple of three. One of the most important features of the model is the joint presence of three light active neutrinos, three additional neutrinos at keV mass scale, and six heavy ones with masses around\textbf{$10^{11}$} GeV. They form a well-motivated part of the spectrum in the sense they address challenging problems related to neutrino oscillation, warm dark matter, and baryogenesis through leptogenesis.Comment: 11 pages. Small corrections and typos fixed. Accepted for publication in PR

Melão.

bitstream/item/124041/1/Rita.pd

Neutrino Decay and Neutrinoless Double Beta Decay in a 3-3-1 Model

In this work we show that the implementation of spontaneous breaking of the lepton number in the 3-3-1 model with right-handed neutrinos gives rise to fast neutrino decay with majoron emission and generates a bunch of new contributions to the neutrinoless double beta decay.Comment: Version accepted for publication in the Phys. Rev.