36,682 research outputs found

    An approach for the detection of point-sources in very high resolution microwave maps

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    This paper deals with the detection problem of extragalactic point-sources in multi-frequency, microwave sky maps that will be obtainable in future cosmic microwave background radiation (CMB) experiments with instruments capable of very high spatial resolution. With spatial resolutions that can be of order of 0.1-1.0 arcsec or better, the extragalactic point-sources will appear isolated. The same holds also for the compact structures due to the Sunyaev-Zeldovich (SZ) effect (both thermal and kinetic). This situation is different from the maps obtainable with instruments as WMAP or PLANCK where, because of the smaller spatial resolution (approximately 5-30 arcmin), the point-sources and the compact structures due to the SZ effect form a uniform noisy background (the "confusion noise"). Hence, the point-source detection techniques developed in the past are based on the assumption that all the emissions that contribute to the microwave background can be modeled with homogeneous and isotropic (often Gaussian) random fields and make use of the corresponding spatial power-spectra. In the case of very high resolution observations such an assumption cannot be adopted since it still holds only for the CMB. Here, we propose an approach based on the assumption that the diffuse emissions that contribute to the microwave background can be locally approximated by two-dimensional low order polynomials. In particular, two sets of numerical techniques are presented containing two different algorithms each. The performance of the algorithms is tested with numerical experiments that mimic the physical scenario expected for high Galactic latitude observations with the Atacama Large Millimeter/Submillimeter Array (ALMA).Comment: Accepted for publication on "Astronomy & Astrophysics". arXiv admin note: substantial text overlap with arXiv:1206.4536 Replaced version is the accepted one and published in A&

    Avaliação de cultivares de aveia branca em Dourados, MS, no período de 2002 a 2004.

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    A aveia branca é uma importante espécie para produção de grãos e forragens no período de outono/inverno, mas é pouco cultivada em Mato Grosso do Sul. Identificar e indicar cultivares com boa adaptação às condições edafoclimáticas da Região Sul de Mato Grosso do Sul podem contribuir para a expansão da área semeada com este cereal.bitstream/item/38722/1/BP200631.pdfDocumento on-line

    Avaliação de cultivares de triticale em Dourados, MS, no período de 2002 a 2004.

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    O triticale, híbrido natural entre o trigo e o centeio, é uma importante espécie para produção de grãos para consumo humano e animal, além de palha para a cobertura do solo, mas é pouco cultivado no período outono/inverno em Mato Grosso do Sul. Identificar e indicar cultivares com boa adaptação às condições edafoclimáticas da Região Sul de Mato Grosso do Sul podem contribuir para a Expansão da área semeada com este cereal.bitstream/item/38724/1/BP200632.pdfDocumento on-line

    Realizing the supersymmetric inverse seesaw model in the framework of R-parity violation

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    If, on one hand, the inverse seesaw is the paradigm of TeV scale seesaw mechanism, on the other it is a challenge to find scenarios capable of realizing it. In this work we propose a scenario, based on the framework of R-parity violation, that realizes minimally the supersymmetric inverse seesaw mechanism. In it the energy scale parameters involved in the mechanism are recognized as the vacuum expectation values of the scalars that compose the singlet superfields N^C\hat N^C and S^\hat S. We develop also the scalar sector of the model and show that the Higgs mass receives a new tree-level contribution that, when combined with the standard contribution plus loop correction, is capable of attaining 125125GeV without resort to heavy stops.Comment: Minor modification of the text. Final version to be published in PL

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

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    We derive the leptonic neutral current in the simplest little Higgs model and compute the contribution of the model to the decay width Ze+eZ \to e^+e^-. Using the precision electroweak data we obtain a strong lower bound f5.6f\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±W^{\prime\pm} and ZZ^{\prime} as being MW±2.6M_{W^{\prime\pm}}\geq 2.6 TeV and MZ3.1M_{Z^{\prime}}\geq 3.1 TeV, respectively. We also present the allowed values of the k=f1/f2k=f_1/f_2 which is the parameter relating the two vacuum expectation values of the scalar triplets in the model, and the μ\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
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