Reduction of Doppler broadening in the Auger electron spectra of fast ion beams: on the refocusing properties of a parallel-plate electrostatic analyser

For a parallel-plate electrostatic analyser, the authors obtain an analytical expression for the optimum exit-slit position that reduces the Doppler line broadening by refocusing and we present a series of computer experiments which simulate our results. The refocusing technique enhances the recorded intensity of Auger lines from projectile states substantially without increasing their energy widths. The method should be extremely useful for the study of high-resolution observations of Auger decays from fast moving ion beams.