The Role of Secondary Electrons in Charged Particle Degradation

A fundamental description of charged particle deposition phenomena must include detailed characterizations of the production and interactions of secondary electrons which arise along the track of a primary particle. Since these secondary electrons predominately have energies below that describable by the Born approximation, one must go beyond the Bethe theory of stopping power and adopt a detailed microscopic approach. In this paper, we review our work involving secondary electron distributions since 1963, beginning with the work of Green and Barth, largely in relation to applications but also in relation to the fitting of experimental data and the testing of theoretical models. In the latter context, we utilize the independent particle model of Green, Sellin, and Zachor in the Born approximation and in the Eikonal approximations. Our past efforts will be reviewed and our current efforts described.