Incident and Exit Charge State Dependence of Secondary Electron Emission from a Carbon Foil by the Passage of Swift Oxygen and Carbon Ions

Abstract

A swift projectile ion travelling in solid targets loses its energy through the excitation of electrons and plasmons. The charge distribution of the projectile ion itself comes close to the state of equilibrium through the charge exchange process with target atoms. Primary electrons produced in the direct ionization of target atoms by the projectile ion give birth to “secondary” electrons through a cascade process. Plasmons also decay into electrons [1]. A part of these electrons diffuse to the surface, overcome the surface potential, and escape from the surface. They are generally called “secondary electrons”, whose energy is mostly below ∼10 eV. The investigation of secondary electrons has a very long history and many review articles have been reported [2] [3]. The parameters observed in the secondary electron emission have been usually an average number, the energy distribution the angular distribution, etc.