Diffraction effects in electron loss from incident on Ar at 78 keV

Abstract

We present an experimental study and a model calculation of the double differential electron-loss cross section produced by 78 keV H 0 colliding with Ar. At this low energy we find a structure in the measured angular and energy distributions that can be interpreted in terms of diffraction of the emitted electrons scattered by the field of the target. Comparison of the observed structure is made with known electron-Ar collision measurements. Our theoretical discussion is based on a quasifree electron scattering model including a partial wave expansion of the active electron. This model is capable of describing the essential features of the experimentally measured distributions.