Angular spectra of rainbow scattering at glancing keV He bombardment of NiAl(1 0 0) surface with transverse energies in the range 1-10 eV

Previous simulations of glancing incidence ion-surface interaction have demonstrated that classical dynamics using the row-model have successfully reproduced multimodal azimuthal and polar spectra. These studies have also shown considerable sensitivity to the form of the interatomic potential thus making it a strong test of the validity of such potentials and even allow deduction of the ion-surface potentials. In these simulations the individual pairwise interactions between the projectile and the target atoms have been replaced by cylindrical potentials.Comparison to numerous experimental studies have confirmed the existence of rainbow scattering phenomena and successfully tested the validity of the cylindrical potential used in these simulations. The use of cylindrical potentials avoids stochastic effects due to thermal displacements and allows faster computer simulations leading to reliable angular distributions.In the present work we extend the row-model to consider scattering from binary alloys. Using He⁺ scattered at glancing incidence from NiAl surfaces, Al or Ni terminated, a faster method has been developed to easily and accurately quantize not only the maximum deflection azimuthal angle but all the singular points in the angular distribution. It has been shown that the influence of the surface termination on the rainbow angle and the inelastic losses is small.     

Crystallographic effects in the kinetic excitation of metal surfaces: A computational study

We present a statistical investigation of the kinetic excitation in atomic collision cascades induced by keV particle impact on metal surfaces. For the model system 5-keV Ag → Ag and a set of 120 impact points, we study the effect of the crystallographic orientation of the target on the average electron temperature evolution at the very surface. Results are discussed in view of secondary ion formation.     

A detailed study of the d + B system for nuclear reaction analysis - Part A: The B(d,p)B reaction in the energy region Ed,lab = 900-2000 keV

The differential cross-sections of the ¹⁰B(d,p_{0,1,2,3,4-5,6}) reactions for the determination of the depth distribution of boron in near-surface layers of materials have been determined in the projectile energy region E_d,lab = 900-2000 keV. The experiment was carried out in energy steps of 25 keV and for eight detector angles between 135° and 170° (in steps of 5°). The obtained experimental data are suitable for nuclear reaction analysis (NRA) studies. A qualitative discussion of the observed cross-section variations through the strong influence of overlapping resonances in the d + ¹⁰B system is also presented.