180° low-energy impact collision ion scattering spectroscopy

Abstract

A low-energy impact collision ion (neutral) scattering spectrometer [(N)ICISS] for exact 180° backscattering has been developed. The energy distribution of the backscattered particles is measured with the time-of-flight method (TOF). 180° backscattering spectra are compared with 145°/140° ones. The nearly identical trajectories for incoming and backscattered particles result in the main advantage of 180° NICISS, namely, a quasi-double focusing effect leads to extremely well behaved peaks in the measured angular patterns.