1,862 research outputs found

    Experimental assessment of the speed of light perturbation in free-fall absolute gravimeters

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    Precision absolute gravity measurements are growing in importance, especially in the context of the new definition of the kilogram. For the case of free-fall absolute gravimeters with a Michelson-type interferometer tracking the position of a free falling body, one of the effects that needs to be taken into account is the speed of light perturbation due to the finite speed of propagation of light. This effect has been extensively discussed in the past, and there is at present a disagreement between different studies. In this work, we present the analysis of new data and confirm the result expected from the theoretical analysis applied nowadays in free-fall gravimeters. We also review the standard derivations of this effect (by using phase shift or Doppler effect arguments) and show their equivalence

    Affine Toda model coupled to matter and the string tension in QCD2_{2}

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    The sl(2)sl(2) affine Toda model coupled to matter (ATM) is shown to describe various features, such as the spectrum and string tension, of the low-energy effective Lagrangian of QCD2_{2} (one flavor and NN colors). The corresponding string tension is computed when the dynamical quarks are in the {\sl fundamental} representation of SU(N) and in the {\sl adjoint} representation of SU(2).Comment: LaTex, 10 pages. Revised version to appear in Phys. Rev.

    Generalized sine-Gordon/massive Thirring models and soliton/particle correspondences

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    We consider a real Lagrangian off-critical submodel describing the soliton sector of the so-called conformal affine sl(3)(1)sl(3)^{(1)} Toda model coupled to matter fields (CATM). The theory is treated as a constrained system in the context of Faddeev-Jackiw and the symplectic schemes. We exhibit the parent Lagrangian nature of the model from which generalizations of the sine-Gordon (GSG) or the massive Thirring (GMT) models are derivable. The dual description of the model is further emphasized by providing the relationships between bilinears of GMT spinors and relevant expressions of the GSG fields. In this way we exhibit the strong/weak coupling phases and the (generalized) soliton/particle correspondences of the model. The sl(n)(1)sl(n)^{(1)} case is also outlined.Comment: 22 pages, LaTex, some comments and references added, conclusions unchanged, to appear in J. Math. Phy

    Higher Grading Conformal Affine Toda Teory and (Generalized) Sine-Gordon/Massive Thirring Duality

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    Some properties of the higher grading integrable generalizations of the conformal affine Toda systems are studied. The fields associated to the non-zero grade generators are Dirac spinors. The effective action is written in terms of the Wess-Zumino-Novikov-Witten (WZNW) action associated to an affine Lie algebra, and an off-critical theory is obtained as the result of the spontaneous breakdown of the conformal symmetry. Moreover, the off-critical theory presents a remarkable equivalence between the Noether and topological currents of the model. Related to the off-critical model we define a real and local Lagrangian provided some reality conditions are imposed on the fields of the model. This real action model is expected to describe the soliton sector of the original model, and turns out to be the master action from which we uncover the weak-strong phases described by (generalized) massive Thirring and sine-Gordon type models, respectively. The case of any (untwisted) affine Lie algebra furnished with the principal gradation is studied in some detail. The example of sl^(n)(n=2,3)\hat{sl}(n) (n=2,3) is presented explicitly.Comment: 28 pages, JHEP styl

    Recommendations and guidelines for applied nutrition experiments in rabbits

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    [EN] The aim of this paper was to draw up a set of recommendations for applied nutrition and feeding trials with rabbits, in relation to certain aspects such as determining the nutritive value of raw materials or diets in growing or reproducing animals, studying digestive physiology and obtaining growth and reproduction parameters. We deal first with animals, size of the sample, housing conditions, diets, handling, measurements, and the data analyses relevant to the design of the experiment are described. Secondly, we give a list of recommended items and include some comments.This study was partly supported by the EUROPEAN COMMISSION (ERAFE program and the COST 848 Action).Fernández-Carmona, J.; Blas, E.; Pascual Amorós, JJ.; Maertens, L.; Gidenne, T.; Xiccato, G.; García, J. (2005). Recommendations and guidelines for applied nutrition experiments in rabbits. World Rabbit Science. 13. doi:10.4995/wrs.2005.516SWORD1

    MÉTODO DE OBTENÇÃO DA MATRIZ DE CONTABILIDADE SOCIAL DO PARANÁ PARA O ANO DE 2000

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    O objetivo deste estudo é apresentar a metodologia de construção da Matriz de Contabilidade Social (MCS) referente ao Estado do Paraná para o ano 2000, e a Matriz de Relações Intersetoriais correspondente, que constituiu a principal base de dados. Também foram utilizados dados da Receita Federal, da Secretaria da Fazenda do Estado do Paraná, da Receita Federal, da Previdência Social, do Instituto Paranaense de Desenvolvimento Econômico Social, e os microdados do Censo Demográfico do Paraná de 2000. A MCS foi construída com 52 linhas e colunas, correspondentes às 41 Atividades econômicas, mais a decomposição do valor adicionado em Salários (desagregados para Empregados com carteira, Empregados sem carteira, Empregadores e Empregados por conta própria), e o Excedente operacional bruto, além das contas Famílias, Governo (Gastos e Receitas), investimentos, Transações com o resto do Brasil, Transações com o exterior, e Demanda total.Insumo-Produção, Matriz de Contabilidade Social, Paraná
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