Lithium Ionization by a Strong Laser Field

We study ab initio computations of the interaction of Lithium with a strong laser field. Numerical solutions of the time-dependent fully-correlated three-particle Schroedinger equation restricted to the one-dimensional soft-core approximation are presented. Our results show a clear transition from non-sequential to sequential double ionization for increasing intensities. Non sequential double ionization is found to be sensitive to the spin configuration of the ionized pair. This asymmetry, also found in experiments of photoionization of Li with synchrotron radiation, shows the evidence of the influence of the exclusion principle in the underlying rescattering mechanism

Nonlinear resonance reflection from and transmission through a dense glassy system built up of oriented linear Frenkel chains: two-level models

A theoretical study of the resonance optical response of assemblies of oriented short (as compared to an optical wavelength) linear Frenkel chains is carried out using a two-level model. We show that both transmittivity and reflectivity of the film may behave in a bistable fashion and analyze how the effects found depend on the film thickness and on the inhomogeneous width of the exciton optical transition.Comment: 26 pages, 9 figure

Método de obtenção qualificada de fenótipos visando à avaliação de genótipos bovinos resistentes ao carrapato Rhipicephalus (Boophilus) microplus.

Formação de grupos de manejo; Determinação correta do momento da mensuração da carga parasitária; Controle parasitário durante o período de avaliação; Padronização da técnica de contagem de carrapatos; Registro de dados; Análise dos dados.bitstream/item/31735/1/CO-75-online.pd

Postmodern Enslavement and Identityanomie: Analogue Modes of Escape from Freedom

The paper puts special emphasis on issue resonances identity shaft, which in postmodern orbit is not conceptual "favorite" for inaugurisanost perception of reality and value structure. Notated perception of the postmodern era, its conceptual articulation seeks to review the traditional structure, the postulates of postmodernism, not more "staff" refers to the evolution of the product technological sphere. Recline on the philosophical background of Jean Baudrillard, the authors discuss the indicative field simulacrum who have no ontological potential and whose affirmative purpose of bringing man to the stage gnoseological passivity. Communication "binder " postmodernity, represents deprivation their own (human) authority as a subjective conviction and questioning the identity of belonging. Therefore, the sense of identity of the modern era is reflected in the fragmentation and fluidity of existence , and it is right to say that a man living in the modern era of floating universe, without a certain criteria. Continuous changes that accompany burdened life courses of individuals and apparently are presented as a privilege and needs actually are hidden mechanisms by which individuals are listed and seduced by easy consumption, obviate indirectly authenticity and originality of its own spirit. It's value skeleton is ideologically determined consumer orientation. DOI: 10.5901/jesr.2014.v4n4p40

Transferring orbital and spin angular momenta of light to atoms

Light beams carrying orbital angular momentum, such as Laguerre-Gaussian beams, give rise to the violation of the standard dipolar selection rules during the interaction with matter yielding, in general, an exchange of angular momentum larger than hbar per absorbed photon. By means of ab initio 3D numerical simulations, we investigate in detail the interaction of a hydrogen atom with intense Gaussian and Laguerre-Gaussian light pulses. We analyze the dependence of the angular momentum exchange with the polarization, the orbital angular momentum, and the carrier-envelope phase of light, as well as with the relative position between the atom and the light vortex. In addition, a quantum-trajectory approach based on the de Broglie-Bohm formulation of quantum mechanics is used to gain physical insight into the absorption of angular momentum by the hydrogen atom

Observation of spontaneous self-channelling of light in air below the collapse threshold

We report the observation of the self-guided propagation of 120 fs, 0.56 mJ infrared radiation in air for distances greater than one meter. In contrast to the known case of filamentation, in the present experiment the laser power is lower than the collapse threshold. Therefore the counter balance between Kerr self focussing and ionization induced defocussing as the stabilizing mechanism is ruled out. Instead, we find evidences of a process in which the transversal beam distribution reshapes into a form similar to a Townes soliton. We include numerical support for this conclusion

Three-dimensional numerical simulation of 1GeV/Nucleon U92+ impact against atomic hydrogen

The impact of 1GeV/Nucleon U92+ projectiles against atomic hydrogen is studied by direct numerical resolution of the time-dependent wave equation for the atomic electron on a three-dimensional Cartesian lattice. We employ the fully relativistic expressions to describe the electromagnetic fields created by the incident ion. The wave equation for the atom interacting with the projectile is carefully derived from the time-dependent Dirac equation in order to retain all the relevant terms.Comment: 12 pages and 7 figures included in the tex