Role of exchange scattering in spin-dependent (e,2e) collisions

Abstract

One of the exciting new developments in the field of electron-impact ionization of atoms lies in the use of spin-polarized electron beams. The development of new technology which allows one to measure increasingly differential cross sections is partially motivated by the fact that the new results would be expected to serve as a more sensitive test of theory. For the last 20 years, spin-polarized electron - atom scattering has provided stringent tests of theory for elastic and inelastic scattering and the new ionization measurements will undoubtedly extend the horizons for this type of work. Probably the most important issue, however, concerns whether or not these sensitive tests can serve as a probe of new physical effects which were not previously observable. In this letter, it is demonstrated that the recent measurements of ionization of xenon using spin-polarized electrons provide information about exchange effects between the projectile electron and atomic charge cloud which would not be seen using unpolarized beams of electrons.