4,871 research outputs found
Matter profile effect in neutrino factory
We point out that the matter profile effect --- the effect of matter density
fluctuation on the baseline --- is very important to estimate the parameters in
a neutrino factory with a very long baseline. To make it clear, we propose the
method of the Fourier series expansion of the matter profile. By using this
method, we can take account of both the matter profile effect and its
ambiguity. For very long baseline experiment, such as L=7332km, in the analysis
of the oscillation phenomena we need to introduce a new parameter ---
the Fourier coefficient of the matter profile --- as a theoretical parameter to
deal with the matter profile effects.Comment: 21 pages, 15 figure
Braided structure of fractional -supersymmetry
It is shown that fractional -superspace is isomorphic to the
limit of the braided line. -supersymmetry is
identified as translational invariance along this line. The fractional
translation generator and its associated covariant derivative emerge as the
limits of the left and right derivatives from the calculus
on the braided lineComment: 8 pages, LaTeX, submitted to Proceedings of the 5th Colloquium
`Quantum groups and integrable systems', Prague, June 1996 (to appear in
Czech. J. Phys.
A new parametrization of the neutrino mixing matrix for neutrino oscillations
In this paper we study three active neutrino oscillations, favored by recent
data from SuperK and SNO, using a new parametrization of the lepton mixing
matrix constructed from a linear combination of the unit matrix , and a
hermitian unitary matrix , that is, .
There are only three real parameters in including the parameter .
It is interesting to find that experimental data on atmospheric neutrino
dictates the angle to be such that the and
mixing is maximal. The solar neutrino problem is solved via the MSW
effect with a small mixing angle, with depending on one small parameter
. The resulting mixing matrix with just two parameters ( and
) predicts that the oscillating probabilities for
and to be equal and of the order . The measurement of CP asymmetries at the proposed Neutrino
Factories would also provide a test of our parametrization.Comment: 10 pages, Retex, no figure
Avaliação da utilização de Nim Indiano em associação com silício e potássio no manejo da Mosca Branca na cultura da soja.
RESUMO: Avaliou-se o uso do produto comercial Organic Neem® e sua associação com o fertilizante à base de silício e potássio Sili-k®, no manejo de Bemisia tabaci (Gennadius) biótipo B (Hemiptera: Aleyrodidae), em casa de vegetação. Realizou-se a aplicação dos tratamentos nas plantas de soja, cultivadas em vasos plásticos, antes e após a infestação artificial pelos adultos da mosca-branca. Os tratamentos foram: Organic Neem® 1L ha-1, Sili-k® 1L ha-1, Organic Neem® 1L ha-1 + Sili-k® 1L ha-1 e testemunha (água). Os resultados mostraram que nenhum dos tratamentos tem ação satisfatória na redução da população da mosca-branca na cultura da soja. ABSTRACT: In this work, the use of the commercial product Organic Neem® and its association with the fertilizer Sili-k® containing silicon and potassium was evaluated in the management of the withefly Bemisia tabaci (Gennadius) biotype B (Hemiptera: Aleyrodidae) under greenhouse conditions. The application of the treatments in soybean plants grown in plastic vases was performed before and after artificial infestation of whitefly adults. The treatments were: Organic Neem® 1L ha-1, Sili-k® 1L ha-1, Organic Neem® 1L ha-1 + Sili-k® 1L ha-1 and control (water). The results showed that none of the tested treatments had satisfactory action in reducing the withefly population in soybean
Efeitos dos inseticidas utilizados no controle de Bemisia tabaci (Gennadius) biótipo B e sua seletividade aos inimigos naturais na cultura da soja.
RESUMO:Nas últimas safras a mosca-branca, Bemisia tabaci biótipo B (Hemiptera: Aleyrodidae) tornou-se praga de importância econômica para a cultura da soja devido à ocorrência de altas infestações e à dificuldade de controle desta praga. Sendo assim, é importante buscar alternativas de manejo com base em um programa de manejo integrado de pragas. Assim, avaliaram-se neste trabalho a eficiência de diferentes inseticidas no controle da mosca-branca em casa-de-vegetação e a seletividade destes aos parasitoides Encarsia formosa, Trichogramma pretiosum e Telenomus remus. Buprofezina 150 g i.a. ha-1 + óleo mineral 0,2% v/v e piriproxifem 100 g. i.a. ha-1 foram consideradas as melhores opções para uso no manejo da mosca-branca devido à boa eficiência de controle da praga associada com a maior seletividade aos parasitoides estudados à exceção de Encarsia formosa para o qual nenhum dos tratamentos avaliados foi classificado como seletivo. Beta-ciflutrina 9,375 +imidacloprido 75 g. i.a. ha-1 foi eficiente no controle de ninfas, mas não foi seletivo aos inimigos naturais avaliados. Em geral, os tratamentos contendo piretróides na sua composição (beta-ciflutrina 9,375 + imidacloprido 75 + espiromesifeno 60 g. i.a. ha-1; beta-ciflutrina 9,375 + imidacloprido 75 g. i.a. ha-1 e lambda-cialotrina 26,5 + tiametoxam 35,25 g i.a. ha-1) foram os mais nocivos aos parasitoides avaliados, portanto seu uso deve ser evitado sempre que possível. ABSTRACT: Effects of insecticides used in Bemisia tabaci (Gennadius) biotype B control and their selectivity to natural enemies in soybean crop in recent crop seasons, the whitefly, Bemisia tabaci biotype B has become a serious pest in soybean crops due to high infestations and its control difficulties. Therefore, it is important to search control alternatives in the integrated pest management approach. Thus, it was evaluated in this study the efficacy of the whitefly control using different insecticides in greenhouse conditions and their selectivity to the parasitoids Encarsia formosa, Trichogramma pretiosum and Telenomus remus. Buprofezin 150 g. a.i.ha-1 + mineral oil 0.2% v/v and pyriproxyfen 100 g. a.i.ha-1 were considered the best options for the whitefly management due to combine good pest control efficacy with higher selectivity to the parasitoids except Encarsia formosa for which no treatment was classified as harmless. Betacyflutrin 9.375 + imidacloprid 75 g. i.a. ha-1 was efficient on controlling whiteflies nymphs but was not harmless to the studied natural enemies. In general, the treatments including pyretroids compounds (betacyflutrin 9.375 + imidacloprid 75 + spiromesifen 60, betacyflutrin 9.375 + imidacloprid 75 and lambda-cyhalothrin 26.5 + thiametoxan 35.25 g. a.i. ha-1) were the most harmful to the evaluated parasitoids and therefore it use should be avoid whenever possible
The Argon Dark Matter Experiment (ArDM)
The ArDM experiment, a 1 ton liquid argon TPC/Calorimeter, is designed for
the detection of dark matter particles which can scatter off the spinless argon
nuclei. These events producing a recoiling nucleus will be discerned by their
light to charge ratio, as well as the time structure of the scintillation
light. The experiment is presently under construction and will be commissioned
on surface at CERN. Here we describe the detector concept and give a short
review on the main detector components.Comment: Proceedings of 4th Patras workshop (DESY) on Axions, Wimps and Wisps
(4 pages, 4 figures
Recent Advances in Chromospheric and Coronal Polarization Diagnostics
I review some recent advances in methods to diagnose polarized radiation with
which we may hope to explore the magnetism of the solar chromosphere and
corona. These methods are based on the remarkable signatures that the
radiatively induced quantum coherences produce in the emergent spectral line
polarization and on the joint action of the Hanle and Zeeman effects. Some
applications to spicules, prominences, active region filaments, emerging flux
regions and the quiet chromosphere are discussed.Comment: Review paper to appear in "Magnetic Coupling between the Interior and
the Atmosphere of the Sun", eds. S. S. Hasan and R. J. Rutten, Astrophysics
and Space Science Proceedings, Springer-Verlag, 200
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