732 research outputs found
On the Integrability and Chaos of an N=2 Maxwell-Chern-Simons-Higgs Mechanical Model
We apply different integrability analysis procedures to a reduced (spatially
homogeneous) mechanical system derived from an off-shell non-minimally coupled
N=2 Maxwell-Chern-Simons-Higgs model that presents BPS topological vortex
excitations, numerically obtained with an ansatz adopted in a special -
critical coupling - parametric regime. As a counterpart of the regularity
associated to the static soliton-like solution, we investigate the possibility
of chaotic dynamics in the evolution of the spatially homogeneous reduced
system, descendant from the full N=2 model under consideration. The originally
rich content of symmetries and interactions, N=2 susy and non-minimal coupling,
singles out the proposed model as an interesting framework for the
investigation of the role played by (super-)symmetries and parametric domains
in the triggering/control of chaotic behavior in gauge systems.
After writing down effective Lagrangian and Hamiltonian functions, and
establishing the corresponding canonical Hamilton equations, we apply global
integrability Noether point symmetries and Painleveproperty criteria to both
the general and the critical coupling regimes. As a non-integrable character is
detected by the pair of analytical criteria applied, we perform suitable
numerical simulations, as we seek for chaotic patterns in the system evolution.
Finally, we present some Comments on the results and perspectives for further
investigations and forthcoming communications.Comment: 18 pages, 5 figure
N=2-Maxwell-Chern-Simons model with anomalous magnetic moment coupling via dimensional reduction
An N=1--supersymmetric version of the Cremmer-Scherk-Kalb-Ramond model with
non-minimal coupling to matter is built up both in terms of superfields and in
a component-field formalism. By adopting a dimensional reduction procedure, the
N=2--D=3 counterpart of the model comes out, with two main features: a genuine
(diagonal) Chern-Simons term and an anomalous magnetic moment coupling between
matter and the gauge potential.Comment: 15 pages, Latex; one reference corrected; To be published in the Int.
J. Mod. Phys.
Efeito de modificadores químicos sobre o comportamento eletrotérmico de selênio em digerido de material vegetal.
A demanda crescente por alimentação balanceada tem despertado interesse em dietas diferenciadas baseadas em alimentos funcionais, os quais possuem propriedades ou substancias bioativas capazes de modular alguma função no organismo. As crucíferas, vegetais com capacidade de absorver altos teores de Se, compõem um grupo de uma série de alimentos desse tipo. A determinação de Se nesses vegetais é de interesse em função tanto de sua importância no metabolismo humano e animal como do ponto de vista de sua toxicidade. Com relação a determinação de Se por espectrometria de absorção atômica com atomização eletrotérmica em forno de grafite (GFAAS), os modificadores químicos convencionais mais citados são: Pd(NO3)2, Mg(NO3)2, Ni(NO3)2, Pd(NO3)2 + Mg(NO3)2,- Pd(NO3)2 + Cd(NO3)2, Pd(NO3)2+ acido ascórbico; Pd (pré-reduzido). Neste trabalho foi avaliada a influência de modificadores químicos sobre o comportamento eletrotérmico de Se em um vegetal da classe das cruciferas (nabo) empregando curvas de pirólise e atomização em presença de Pd(II), Ni(II), Mg(II), Pd pré-reduzido e das misturas Pd(II)/Mg(II) e Pd(II)/Cd(II). Foram preparadas soluções analíticas contendo 20 pg Se L-1 em meio 0,014 mol L-1 HNO3 e 30 pg Se L -1 em digerido do material vegetal
Self-dual vortices in a Maxwell-Chern-Simons model with non-minimal coupling
We find self-dual vortex solutions in a Maxwell-Chern-Simons model with
anomalous magnetic moment. From a recently developed N=2-supersymmetric
extension, we obtain the proper Bogomol'nyi equations together with a Higgs
potential allowing both topological and non-topological phases in the theory.Comment: 12 pages, 9 figures, 2 tables; some typos corrected, one reference
updated. To be published in the Int. J. Mod. Phys. A (1999
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