1,457 research outputs found
Diagnóstico dos processos tecnológicos utilizados no manejo integrado de pragas da cana-de-açúcar em El Salvador.
bitstream/item/81420/1/Doc-174.pd
Influence of second-order corrections to the energy-dependence of neutrino flavor conversion formulae
We discuss the {\em intermediate} wave-packet formalism for analytically
quantifying the energy dependence of the two-flavor conversion formula that is
usually considered for analyzing neutrino oscillations and adjusting the
focusing horn, target position and/or detector location of some flavor
conversion experiments. Following a sequence of analytical approximations where
we consider the second-order corrections in a power series expansion of the
energy, we point out a {\em residual} time-dependent phase which, in addition
to some well known wave-packet effects, can subtly modify the oscillation
parameters and limits. In the present precision era of neutrino oscillation
experiments where higher precision measurements are required, we quantify some
small corrections in neutrino flavor conversion formulae which lead to a
modified energy-dependence for oscillations.Comment: 13 pages, 3 figure
Desenvolvimento de um software para análise da compatibilidade de nematoides entomopatogênicos (Nematoda: Steinernematidae e Heterorhabditidae) com produtos fitossanitários em laboratório.
Theoretical correlation between possible evidences of neutrino chiral oscillations and polarization measurements
Reporting about the formalism with the Dirac equation we describe the
dynamics of chiral oscillations for a fermionic particle non-minimally coupling
with an external magnetic field. For massive particles, the chirality and
helicity quantum numbers represent different physical quantities of
representative importance in the study of chiral interactions, in particular,
in the context of neutrino physics. After solving the interacting Hamiltonian
(Dirac) equation for the corresponding {\em fermionic} Dirac-{\em type}
particle (neutrino) and quantifying chiral oscillations in the Dirac wave
packet framework, we avail the possibility of determining realistic neutrino
chirality conversion rates by means of (helicity) polarization measurements. We
notice that it can become feasible for some particular magnetic field
configurations with large values of {\boldmath} orthogonal to the direction
of the propagating particle.Comment: 12 pages, 2 figure
Parasitismo de Opsiphanes sp. (Lepidoptera: Nymphalidae) por Conura (Conura) maculata (Fabricius, 1787) (Hymenoptera: Chalcididae) no estado de Alagoas, Brasil.
Manejo integrado da broca-do-olho-do-coqueiro Rhynchophorus palmarum L. (Coleoptera: Curculionidae).
O gênero Rhynchophorus é relatado causando dano em palmeiras em quase toda a região tropical do Planeta. Três espécies ocorrem nas Américas: R. cruentatus na Florida, costa sudeste dos Estados Unidos e Bahamas; R. palmarum no México, Américas Central e do Sul, e sul das Antilhas; e R. ritcheri no Peru (GIBLIN-DAVIS et al., 2013).bitstream/item/125475/1/Cot-141.pd
Aspectos biológicos e manejo da Cochonilha-transparente aspidiotus destructor e do Pulgão-preto Cerataphis Lataniae em coqueiro.
bitstream/item/142578/1/cot-177.1pdf.pd
Energy localization on q-tori, long term stability and the interpretation of FPU recurrences
We focus on two approaches that have been proposed in recent years for the
explanation of the so-called FPU paradox, i.e. the persistence of energy
localization in the `low-q' Fourier modes of Fermi-Pasta-Ulam nonlinear
lattices, preventing equipartition among all modes at low energies. In the
first approach, a low-frequency fraction of the spectrum is initially excited
leading to the formation of `natural packets' exhibiting exponential stability,
while in the second, emphasis is placed on the existence of `q-breathers', i.e
periodic continuations of the linear modes of the lattice, which are
exponentially localized in Fourier space. Following ideas of the latter, we
introduce in this paper the concept of `q-tori' representing exponentially
localized solutions on low-dimensional tori and use their stability properties
to reconcile these two approaches and provide a more complete explanation of
the FPU paradox.Comment: 38 pages, 7 figure
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