ALBEDO AND ENERGY ALBEDO OF LOW-ENERGY ELECTRONS FROM BULK MATERIALS

The (energy) albedo is also referred to as the (energy) reflection coefficient. In this paper, a Monte Carlo model of single elastic collisions, incorporating accurate elastic cross sections, has been used to calculate the albedo and energy albedo of low-energy electrons from bulk materials. The initial electron energy T0 in the calculations covers a range of 1 to 100 keV. The elastic-scattering cross sections were obtained using a relativistic partial wave method. For describing the electron energy loss in inelastic collisions, the Bethe stopping power is used for electron transport with T0 = 10-100 keV, and stopping power data from Ashley et al. have been adopted for one with T0 = 1-10 keV. The materials explored include carbon, aluminium, tantalum and gold, and both normal and oblique incidences were studied. Calculated results are in good agreement with experimental measurements. In comparison with multiple-scattering models (the so-called condensed history scheme), the model based on single elastic collisions gives more reliable predictions. The influence of cross-section data on Monte Carlo results is also discussed. © 1990.