Изучение критического угла каналирования ионов активных металлов через тонкие пленки алюминия

The spatial distributions of ions (K+, Na+) passed through thin polycrystalline and single-crystalline Al films with the thickness from 180 to 600 Å and critical channeling angles have been studied. The ion energies have been varied within the range E0 = 10-30 keV. It has been shown that an increase in the energy of the primary ion beam leads to a decrease in the width of the maxima of the angular distribution, which is associated with a decrease in the critical channeling angle ψcr. It has been found that the value ψcr does not exceed 4-50 for axial channeling and 9-100 for planar channeling.

Influence of nuclear multiple scattering on axially channeled protons in a bent crystal

The influence of nuclear multiple scattering on axially channeled protons with an energy of 7 TeV through a bent <100> Si crystal, is presented in this paper. The aims of the investigation are the processes correlated to the axial channeling, such as dechanneling, angular distributions and energy loss distribution. The data for these processes are generated via the numerical solution of the proton equations of motion in the transverse plane and the computer simulation method. In the simulations, the crystal thickness is varied from 1 to 5 mm while the bending angle is varied from 0 to 20 mrad. The increasing of the transverse energy of axially channeled protons is due to its multiple scattering by atomic strings and the bending dechanneling mechanism. The analysis of the generated data shows that in the cases we are considering, the dechanneling function, the energy loss spectra, and the angular distributions do not undergo to any significant changes when the effect of nuclear multiple scattering is included in the ion-atom interactions.