Absolute triply differential cross section for K-shell ionisation by relativistic electron impact for high atomic number

Abstract

The absolute triply differential cross section for K-shell ionisation by 500 keV electron impact for high atomic number (Z=73) was measured as a function of the energy sharing between outgoing electrons. By using a two-parameter set-up, electron-electron coincidences in a wide energy sharing range could be registered in the same run. Scattering angle pairs of 40 degrees /-20 degrees and 30 degrees /-30 degrees , respectively, were used in a coplanar geometry. The results show the inadequacy of the theory of Das and Konar (1974) for the present parameters.