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

Axion Like Particles and the Inverse Seesaw Mechanism

Light pseudoscalars known as axion like particles (ALPs) may be behind physical phenomena like the Universe transparency to ultra-energetic photons, the soft $\gamma$-ray excess from the Coma cluster, and the 3.5 keV line. We explore the connection of these particles with the inverse seesaw (ISS) mechanism for neutrino mass generation. We propose a very restrictive setting where the scalar field hosting the ALP is also responsible for generating the ISS mass scales through its vacuum expectation value on gravity induced nonrenormalizable operators. A discrete gauge symmetry protects the theory from the appearance of overly strong gravitational effects and discrete anomaly cancellation imposes strong constraints on the order of the group. The anomalous U$(1)$ symmetry leading to the ALP is an extended lepton number and the protective discrete symmetry can be always chosen as a subgroup of a combination of the lepton number and the baryon number.Comment: 29pp. v4: published version with erratum. Conclusions unchange

Generation of higher derivatives operators and electromagnetic wave propagation in a Lorentz-violation scenario

We study the perturbative generation of higher-derivative operators as corrections to the photon effective action, which are originated from a Lorentz violation background. Such corrections are obtained, at one-loop order, through the proper-time method, using the zeta function regularization. We focus over the lowest order corrections and investigate their influence in the propagation of electromagnetic waves through the vacuum, in the presence of a strong, constant magnetic field. This is a setting of experimental relevance, since it bases active efforts to measure non linear electromagnetic effects. After surprising cancellations of Lorentz violating corrections to the Maxwell's equation, we show that no effects of the kind of Lorentz violation we consider can be detected in such a context.Comment: v2: 13 pages, no figures, section IV considerably rewritten, main results unchanged and are now obtained in a simpler way. To appear in PL

SP mountain data analysis

An analysis of synthetic aperture radar data of SP Mountain was undertaken to demonstrate the use of digital image processing techniques to aid in geologic interpretation of SAR data. These data were collected with the ERIM X- and L-band airborne SAR using like- and cross-polarizations. The resulting signal films were used to produce computer compatible tapes, from which four-channel imagery was generated. Slant range-to-ground range and range-azimuth-scale corrections were made in order to facilitate image registration; intensity corrections were also made. Manual interpretation of the imagery showed that L-band represented the geology of the area better than X-band. Several differences between the various images were also noted. Further digital analysis of the corrected data was done for enhancement purposes. This analysis included application of an MSS differencing routine and development of a routine for removal of relief displacement. It was found that accurate registration of the SAR channels is critical to the effectiveness of the differencing routine. Use of the relief displacement algorithm on the SP Mountain data demonstrated the feasibility of the technique

Avaliação de produtividade de melancia de frutos pequenos no submédio do São Francisco, em função da densidade de plantio.

Suplemento. Edição dos Trabalhos do 49 Congresso Brasileiro de Olericultura, Águas de Lindóia, ago. 2009

Primeiro registro de Seticornuta Morley (Hymenoptera, Ichneumonidae, Metopiinae) do Brasil e descrição de uma nova espécie.

A new species of Seticornuta from Brazil is described and illustrated, the frst record of this genus for the Brazilian fauna. This new species was found in a study that aimed to enhance knowledge of the Brazilian fauna of Metopiinae, analysing samples from the hydrographic basin of Rio Mogi Guaçu. A diagnosis, along with distribution information for Seticornuta species are provided