Inverse type II seesaw mechanism and its signature at the LHC and ILC

The advent of the LHC, and the proposal of building future colliders as the ILC, both programmed to explore new physics at the TeV scale, justifies the recent interest in studying all kind of seesaw mechanisms whose signature lies on such energy scale. The natural candidate for this kind of seesaw mechanism is the inverse one. The conventional inverse seesaw mechanism is implemented in an arrangement involving six new heavy neutrinos in addition to the three standard ones. In this paper we develop the inverse seesaw mechanism based on Higgs triplet model and probe its signature at the LHC and ILC. We argue that the conjoint analysis of the LHC together with the ILC may confirm the mechanism and, perhaps, infer the hierarchy of the neutrino masses.Comment: 24 pages, 22 figure

A new data reduction scheme to obtain the mode II fracture properties of Pinus Pinaster wood

In this work a numerical study of the End Notched Flexure (ENF) specimen was performed in order to obtain the mode II critical strain energy released rate (GIIc) of a Pinus pinaster wood in the RL crack propagation system. The analysis included interface finite elements and a progressive damage model based on indirect use of Fracture Mechanics. The difficulties in monitoring the crack length during an experimental ENF test and the inconvenience of performing separate tests in order to obtain the elastic properties are well known. To avoid these problems, a new data reduction scheme based on the equivalent crack concept was proposed and validated. This new data reduction scheme, the Compliance-Based Beam Method (CBBM), does not require crack measurements during ENF tests and additional tests to obtain elastic properties.FCT - POCTI/EME/45573/200

Finite element analysis of the ECT test on mode III interlaminar fracture of carbon-epoxy composite laminates

In this work a parametric study of the Edge Crack Torsion (ECT) specimen was performed in order to maximize the mode III component (GIII) of the strain energy release rate for carbon-epoxy laminates. A three-dimensional finite element analysis of the ECT test was conducted considering a [90/0/(+45/-45)2/(-45/+45)2/0/90]S lay-up. The main objective was to define an adequate geometry to obtain an almost pure mode III at crack front. The geometrical parameters studied were specimen dimensions, distance between pins and size of the initial crack. The numerical results demonstrated that the ratio between the specimen length and the initial crack length had a significant effect on the strain energy release rate distributions. In almost all of the tested configurations, a mode II component occurred near the edges but it did not interfere significantly with the dominant mode III state.FCT - POCTI/EME/45573/200

Sterile neutrino dark matter, CDMS-II and a light Higgs boson

We add a singlet right handed neutrino plus a charged and a neutral singlet scalars to the standard model. This extension includes a discrete symmetry such that we obtain a heavy sterile neutrino which couples only to the electron and the new scalars. In this sense the singlet neutrino does not mix with ordinary ones and thus has no effect on Big Bang Nucleosynthesis. However, such sterile neutrino can be in equilibrium with electroweak particles in the early Universe due to its couplings to electrons and also because the Higgs boson mixes with the singlet scalars. We obtain that the sterile neutrino constitutes a dark matter candidate and analyze its direct detection in the light of current experiments. Our results show that if such a sterile neutrino is realized in nature, and CDMS-II experiment confirms its positive signal, dark matter demands a rather light Higgs boson with new Physics at some 500 GeV scale.Comment: 16 pages, 13 figures, uses axodraw.st

Competição de cultivares de caupi de hábito nao ramador no Território Federal de Amapá.

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A Simple Realization of the Inverse Seesaw Mechanism

Differently from the canonical seesaw mechanism, which is grounded in grand unified theories, the inverse seesaw mechanism lacks a special framework that realizes it naturally. In this work we advocate that the 3-3-1 model with right-handed neutrinos has such an appropriate framework to accommodate the inverse seesaw mechanism. We also provide an explanation for the smallness of the $\mu$ parameter and estimate the branching ratio for the rare lepton flavor violation process $\mu \rightarrow e\gamma$.Comment: About 14pages, no figures, basis corrected, to appear at the PR