M. Alfaz Uddin

Chapter 6 – Electron Impact Inner-Shell Ionization of Atoms

Electron impact inner-shell ionization cross-section (EIICS) calculations of neutral atoms with atomic numbers Z = 6–92 for K-shell, Z = 18–92 for L-shell, and Z = 79–92 for M-shell have been reviewed. In this work, the evaluations of the EIICS are discussed using our recently propounded easy-to-use models that are found adequately successful in describing the experimental cross sections. The selection of the range of atomic number Z for different inner-shells was guided by the availability of the EIICS data either from experiments or from rigorous quantal calculations. Details of the models have been presented and their findings are compared with the experimental and other theoretical results. Our models describe the experimental results nicely for K-, L-, and M-shell ionization for Z ≤ 92 in the energy range E ≤ 2 GeV.

Elastic scattering of electrons and positrons by cadmium atoms

ABSTRACT The differential, integrated elastic, total and momentum transfer cross sections along with Sherman function for the elastic scattering of electrons and positrons by cadmium atoms have been evaluated from the partial wave solution of the Dirac relativistic scattering equations for a projectile-atom complex potential at the energy range 6.4 eV < E < 1.0 keV. For various scattering quantities, a comparison of our results exhibits better agreement with the experimental data than the other available theoretical values. GRAPHICAL ABSTRACT

Electron impact M-subshell ionization of atoms at relativistic energies

We propose an extension of our recently modified simplified-improved-binary-encounter dipole (MUIBED) model [1] suitable even for relativistic energies. This new model (XMUBED) is applied to calculate the electron impact single M-subshell ionization cross-sections for atomic targets with various charges Z (79 ≤ Z ≤ 92). The parameters of the MUIBED model for the M-shell ionization calculations are modified to account well for fourteen atomic targets (between Au and U) for the inner M-subshell ionization cross sections.

Electron impact single ionization of mono- and di-positive ions

The electron impact ionization cross-sections of mono- and di-positive ionic targets are calculated using a second version of the modified binary-encounter-dipole (MBED) model, previously reported [M A Uddinet al, J. Phys.B37, 1909 (2004)]. The present version differs from the previous one in the scale factor of the Burgess denominator and is applicable to targets with chargesq = 1 and 2. The MBED in the present form is found to work well for 11 ionic targets ranging from Be+ to K+ and complements its previous version valid for targets withq s> 2