We studied forward and backward electron ejection from carbon foils penetrated by swift ions ͑energy range, 20 keV/nucleon-74 MeV/nucleon; projectiles, H-U͒ over four orders of magnitude of electronic energy loss ͑0.01-25 keV/nm͒. Ejection of fast electrons from primary ionization and subsequent energy dissipation by secondary cascades are found to be asymmetric. Electronic energy deposition by swift ions is thus different at the entrance surface, in the solid's bulk, and at the exit surface. The effect strongly increases with projectile atomic number due to an increasing contribution of close collisions and enhanced fast-electron ejection.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.