RUTHERFORD BACKSCATTERING BEYOND THE SINGLE SCATTERING MODEL

This contribution deals with the influence of plural and multiple scattering on Rutherford backscattering (RBS) spectra, investigated by Monte Carlo simulation. Multiple scattering leads to a spread in path length and scattering angle of the projectiles scattered into the detector. Thus, the low energy edge of the RBS spectrum may be shifted noticeably. Also the kinematic energy loss and the shape of the RBS peak are influenced. Due to plural scattering, excessive projectile path lengths may occur, producing the ''low energy background'', which also extends within the RBS peak. In cases, where the kinematic energy loss is large, projectiles are detectable at energies higher thin the expected RBS high energy edge (''high energy background''). Plural scattering also increases the number of projectiles contributing to the RBS peak.