Influence of surface roughness on conversion electron scattering and its effect in CEMS and DCEMS analysis

The effect of surface roughness on the scattering and energy loss of internal conversion electrons has been studied by Monte Carlo simulation. The initial electron energy is 7.3 keV, corresponding to the K-conversion electrons in ⁵⁷Fe CEMS and DCEMS, or to a ⁵⁷Co source. Roughness is modelled by a surface oscillation with amplitudes and wavelengths in the range ∼ 10 ¹-10 ⁴ Å. Total transmission, angular distributions, energy loss profiles and transmission into restricted energy and angular intervals (DCEMS weight functions) have been simulated, assuming Fe as scattering material. The results show that it may be possible to estimate surface roughness from the energy loss profiles measured at different angles. Conditions for the use of conventional (plane surface) weight functions in ⁵⁷Fe CEMS and DCEMS are obtained.