QCD phenomenology with infrared finite SDE solutions

Recent progress in the solution of Schwinger-Dyson equations (SDE), as well as lattice simulation of pure glue QCD, indicate that the gluon propagator and coupling constant are infrared (IR) finite. We discuss how this non-perturbative information can be introduced into the QCD perturbative expansion in a consistent scheme, showing some examples of tree level hadronic reactions that successfully fit the experimental data with the gluon propagator and coupling constant depending on a dynamically generated gluon mass. This infrared mass scale acts as a natural cutoff and eliminates some of the ad hoc parameters usually found in perturbative QCD calculations. The application of these IR finite Green's functions in the case of higher order terms of the perturbative expansion is commented. © Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence.

Context-sensitive analysis without calling-context

Since Sharir and Pnueli, algorithms for context-sensitivity have been defined in terms of 'valid' paths in an interprocedural flow graph. The definition of valid paths requires atomic call and ret statements, and encapsulated procedures. Thus, the resulting algorithms are not directly applicable when behavior similar to call and ret instructions may be realized using non-atomic statements, or when procedures do not have rigid boundaries, such as with programs in low level languages like assembly or RTL. We present a framework for context-sensitive analysis that requires neither atomic call and ret instructions, nor encapsulated procedures. The framework presented decouples the transfer of control semantics and the context manipulation semantics of statements. A new definition of context-sensitivity, called stack contexts, is developed. A stack context, which is defined using trace semantics, is more general than Sharir and Pnueli's interprocedural path based calling-context. An abstract interpretation based framework is developed to reason about stack-contexts and to derive analogues of calling-context based algorithms using stack-context. The framework presented is suitable for deriving algorithms for analyzing binary programs, such as malware, that employ obfuscations with the deliberate intent of defeating automated analysis. The framework is used to create a context-sensitive version of Venable et al.'s algorithm for analyzing x86 binaries without requiring that a binary conforms to a standard compilation model for maintaining procedures, calls, and returns. Experimental results show that a context-sensitive analysis using stack-context performs just as well for programs where the use of Sharir and Pnueli's calling-context produces correct approximations. However, if those programs are transformed to use call obfuscations, a contextsensitive analysis using stack-context still provides the same, correct results and without any additional overhead. © Springer Science+Business Media, LLC 2011.

DN interaction from meson exchange

A model of the DN interaction is presented which is developed in close analogy to the meson-exchange KN potential of the Jülich group utilizing SU(4) symmetry constraints. The main ingredients of the interaction are provided by vector meson (ρ, ω) exchange and higher-order box diagrams involving D *N, DΔ, and D *Δ intermediate states. The coupling of DN to the π Λ c and π Σ c channels is taken into account. The interaction model generates the Λ c(2595)-resonance dynamically as a DN quasi-bound state. Results for DN total and differential cross sections are presented and compared with predictions of two interaction models that are based on the leading-order Weinberg-Tomozawa term. Some features of the Λ c(2595)-resonance are discussed and the role of the near-by π Σ c threshold is emphasized. Selected predictions of the orginal KN model are reported too. Specifically, it is pointed out that the model generates two poles in the partial wave corresponding to the Λ(1405)-resonance. © 2011 SIF, Springer-Verlag Berlin Heidelberg.

Possíveis conseqüências na evolução de Triton em queda

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Métodos numéricos para o retoque digital

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Sistemas dinâmicos discretos: análise de estabilidade

Pós-graduação em Matemática Universitária - IGCE

Problemas fitossanitários e crescimento de duas cultivares de café durante o primeiro ano em experimento FACE (“Free Air Carbon Dioxide Enrichment”)

Pós-graduação em Agronomia (Proteção de Plantas) - FCA

Tópicos em teoria quântica de campos

Pós-graduação em Física - IFT

Fabricação e caracterização estrutural de filmes evaporados de ftalocianinas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Formalismo de Hamilton-Jacobi generalizado: teorias de campos com derivadas de ordem superior

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

O papel da nominalização no continuum categorial

A continuidade categorial é uma propriedade indiscutível da linguagem para a tradição funcionalista, que a trata como um verdadeiro universal linguístico. Além de buscar evidência sistemática para a comprovação desse axioma, o principal objetivo deste trabalho é analisar a estrutura argumental da nominalização, num esforço concentrado por demonstrar que esse mesmo princípio universal é metodologicamente útil e teoricamente válido para postular relações intralinguísticas de continuidade categorial mesmo entre classes aparentemente discretas como as de substantivo e verbo. A trajetória percorrida para a sustentação da hipótese da continuidade categorial passa necessariamente pela comprovação de uma hipótese secundária, a de preservação de valência, postulada por Dik (1985; 1997), segundo a qual a estrutura argumental é parte constitutiva da nominalização. Essa busca não teria êxito se a trajetória percorrida não utilizasse um atalho necessário, representado pela teoria prototípica de categorização. De fato, postular a existência de categorias intermediárias, como a de nominalização, implica necessariamente a existência de membros mais prototípicos de uma categoria. A existência de estrutura argumental, que sinaliza a representação de entidades de ordem superior, permite aproximar a nominalização de membros não-prototípicos da categoria dos verbos como formas não-finitas, enquanto a ausência de estrutura argumental, que sinaliza a representação de uma entidade de primeira ordem, permitiu aproximá-lo de membros prototípicos da categoria dos substantivos

The dynamic implementation of non-overt arguments in nominalizations

Valency is an inherent property of nominalizations representing higher-order entities, and as such it should be included in their underlying representation. On the basis of this assumption, I postulate that cases of non-overt arguments, which are very common in Brazilian Portuguese and in many other languages of the world, should be considered a special type of valency realization. This paper aims to give empirical support to this postulate by showing that non-overt arguments are both semantically and pragmatically motivated. The semantic and pragmatic motivations for non-overt arguments may be accounted for by the dynamic implementation of the FDG model. I argue that the way valency is realized by means of non-overt arguments suggests a strong parallelism between nominalizations and other types of non-finite embedded constructions – like infinitival and participial ones. By providing empirical evidence for this parallelism I arrive at the conclusion that there are at least three kinds of non-finite embedded constructions, rather than only two, as suggested by Dik (1997).

Studies of azimuthal dihadron correlations in ultra-central PbPb collisions at=2.76 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Structural, electronic and optical properties of Fe(III) complex with pyridine-2,6-dicarboxylic acid: A combined experimental and theoretical study

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influence of solvent on the morphology and photocatalytic properties of ZnS decorated CeO2 nanoparticles

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)