Laser-assisted electron-atom collisions

Abstract

New insights into our understanding of the fundamental electron-atom collision process have been made possible by combining the use of highly monochromatic electron beams and intense laser radiation. The paper reviews recent experimental effort in laser-assisted electron scattering with particular emphasis upon free-free (inverse bremsstrahlung) collisions. The excitation of an atom by simultaneous absorption of photon(s) and kinetic energy from the incident electron, the so-called SEPE process, is also discussed. The role of resonance formation in such collision cross sections is of major importance and reveals new information on the dynamics of the collision process. Modern theoretical treatments of such laser-assisted collisions are examined and shown to be only partially successful in explaining modern experimental results. The need for more rigorous theoretical calculations is clearly shown.