Three-body description of direct nuclear reactions: Comparison with the continuum discretized coupled channels method

The continuum discretized coupled channels (CDCC) method is compared to the exact solution of the three-body Faddeev equations in momentum space. We present results for: i) elastic and breakup observables of d-12C at E_d=56 MeV, ii) elastic scattering of d-58Ni at E_d=80 MeV, and iii) elastic, breakup and transfer observables for 11Be+p at E_{11Be}/A=38.4 MeV. Our comparative studies show that, in the first two cases, the CDCC method is a good approximation to the full three-body Faddeev solution, but for the 11Be exotic nucleus, depending on the observable or the kinematic regime, it may miss out some of the dynamic three-body effects that appear through the explicit coupling to the transfer channel.Comment: 12 pages, 10 figures, accepted for publication in Physical Review

Multiple scattering effects in quasi free scattering from halo nuclei: a test to Distorted Wave Impulse Approximation

Full Faddeev-type calculations are performed for $^{11}$Be breakup on proton target at 38.4, 100, and 200 MeV/u incident energies. The convergence of the multiple scattering expansion is investigated. The results are compared with those of other frameworks like Distorted Wave Impulse Approximation that are based on an incomplete and truncated multiple scattering expansion.Comment: 7 pages, 16 figures, to be published in Phys. Rev.

Very High Mach Number Electrostatic Shocks in Collisionless Plasmas

The kinetic theory of collisionless electrostatic shocks resulting from the collision of plasma slabs with different temperatures and densities is presented. The theoretical results are confirmed by self-consistent particle-in-cell simulations, revealing the formation and stable propagation of electrostatic shocks with very high Mach numbers ($M \gg 10$), well above the predictions of the classical theories for electrostatic shocks.Comment: 6 pages, submitted to Phys. Rev. Let

Fuzzy short-run control charts

Statistical control charts are useful tools in monitoring the state of a manufacturing process. Control charts are used to plot process data and compare it to the limits set for the process. Points plotting outside these limits indicate an out-of-control condition. Standard control charting procedures, however, are limited in that they cannot take into account the case when data is of a fuzzy nature. Another limitation of standard charting methods is when the data produced by the process is short-run data. Often, the situation where the data is short-run occurs in conjunction with data that is considered fuzzy. This paper dicusses the development of a fuzzy control chartting technique, called short-Run α-cut p Control Chart, to account for fuzzy data in a short-run situation. The developed chart parameters accounted for the fuzzy nature of the data in a short-run situation. The parameters were validated by comparing the false alarm rates for various combinations of subgroup numbers (m) and subgroup sizes (n). It was shown that for every combination of m and n, the Short-Run α-cut p Control Chart limits produced a lower false alarm rate than that of the standard fuzzy α-cut control chart.Peer Reviewe

Distribuição geográfica do Crysoperla externa no Brasil a partir de cenários de temperatura atual e futuros.

O presente estudo visou uma melhor compreensão da distribuição geográfica do Chrysoperla externa com base nos cenários de temperatura do IPCC. O crisopideo apresenta ampla distribuição geográfica, e é usado como agende de controle biológico de pragas em lavouras. Para a elaboração dos mapas temáticos referentes aos estudos, utilizou-se as médias mensais de temperatura do IPCC (Intergovernamental Panel on Climate Change). Estas médias são divididas em 7 mapas raster que contêm em cada pixel, com tamanho de 30? (meio grau), a média de temperatura estimada. O primeiro mapa mostra a média atual de temperatura, a qual foi calculada através dos dados obtidos entre 1961 e 1990. Os outros mapas trazem um prognóstico das médias centradas em 2020, 2050 e 2080, sendo que para cada cenário se tem uma perspectiva otimista (o aquecimento global não será tão intenso) e o outro traz uma ótica pessimista (o aquecimento global trará modificações drásticas ao clima global). O software ArcGIS foi utilizado na separação das classes de temperatura e na confecção dos mapas finais. Os resultados encontrados apontam para uma diminuição da área de atuação nas regiões Norte e Nordeste do predador à medida que a média da temperatura aumenta, tornando essas regiões não favoráveis ou pouco favoráveis a sobrevivência do inseto

Coherent photon assisted cotunneling in a Coulomb blockade device

We study cotunneling in a double junction Coulomb blockade device under the influence of time dependent potentials. It is shown that the ac-bias leads to photon assisted cotunneling which in some cases may dominate the transport. We derive a general non-perturbative expression for the tunneling current in the presence of oscillating potentials and give a perturbative expression for the photon assisted cotunneling current.Comment: Replaced with a longer paper which includes a non-perturbative calculation. 13 pages with 1 figure. To be published in Physical Review