Effect of orbiting resonance on the elastic differential cross sections

Abstract

AbstractsThe effects of orbiting resonances on elastic differential cross sections are investigated for the 6) model potential. The elastic differential cross section consists of three terms: a resonance term, a potential scattering term and an interference term. The interference term has a significant effect only at small angles of the differential cross section. The importance of the potential scattering term depends proportionally upon the orbiting resonance energy. For the low-lying orbiting resonance states, the resonance term is the dominant term, but at higher energy it appears only in the backward differential cross sections. Generally, by fitting the large angle differential cross sections, the resonance orbital angular momentum can be estimated.On Ctudie les effets de rksonances "orbiting" sur les sections efficaces diffCrentielles Clastiques pour le potentiel de modttle de Lennard-Jones (12, 6). Cette section efficace consiste de trois termes: un terme d e rCsonance, un terme de diffusion par le potentiel et un terme d'interfkrence. Ce dernier terme n'a un effet significatif qu'h des petits angles de la section efficace difftrentielle. L'importance du second terme dCpend d'une faGon proportionnelle de l'tnergie de rksonance. Pour les Ctats de resonance profonds le terme de rCsonance domine, mais pour des Cnergies plus hautes on ne le trouve que dans les sections efficaces rttrogrades. E n gCnCral on peut estimer le moment cinktique de la rtsonance i i partir des sections efficaces de grands angles. Die Effekte von "Orbiting"-Resonanzen auf elastische differentielle Querschnitte werden fur das Lennard-Jones'sche (12, 6)-Modellpotential untersucht. Dieser Querschnitt enthalt drei Glieder: in Resonanzglied, ein Potentialstreuungsglied und ein Interferenzglied. Das letzte Glied hat nur an kleinen Winkeln des Querschnitts einen bemerkbaren Effekt. Die Bedeutung des Potentialstreuungsglied hangt proportional von der Resonanzenergie ab. Fur die tiefliegenden Resonanzzustande dominiert das Resonanzglied, aber an hoheren Energien kommt es nur in den Ruckwartsquerschnitten vor. In allgemeinen kann der Bahndrehimpulsmoment der Resonanz von den Grosswinkelquerschnitten abgeschatzt werden.

Imaging resonances in low-energy NO-He inelastic collisions

“…At the resonance energies, the DCSs contain specific information on the partial-wave dynamics of the collision process-the relation between l in , l res , and l out . If the scattering were purely determined by a resonance without any background, the scattering matrix S would be given by the Breit-Wigner formula, which was originally developed for neutron scattering in 1936 and nowadays is frequently used to describe scattering processes in high-energy particle physics (24,25). However, in most cases and also in our experiments, the observed ICSs and DCSs result from an interference between resonance and background contributions.…”

Imaging resonances in low-energy NO-He inelastic collisions

“…At the resonance energies, the DCSs contain unique information on the partial wave dynamics of the collision process, i.e., the relation between ℓ in , ℓ res , and ℓ out . If the scattering were purely determined by a resonance without any background, the scattering matrix S would be given by the Breit-Wigner formula, originally developed for neutron scattering in 1936 and nowadays frequently used to describe scattering processes in high energy particle physics (24,25). However, in most cases and also in our experiments, the observed ICSs and DCSs result from an interference between resonance and background contributions.…”