title: Radiation damage due to knock-on processes on carbon foils cooled to liquid helium temperature.
abstract: Radiation damage on a holey carbon foil was investigated in an electron microscope with a superconducting lens system, where the temperature of the specimen and its environment initially was 4 K. Due to an electron dose of 2 X 10(4) As/cm2 the diameter of a hole increased 5 nm. Rough calculations show that this increase can be ascribed to knock-on processes. Estimates of the rise in specimen temperature during the irradiation are given.
mesh_terms: D002244:Carbon / Q000528:radiation effects*; D003080:Cold Temperature; D004583:Electrons; D007909:Lenses; D008433:Mathematics; D008854:Microscopy, Electron
chemical_list: D002244:Carbon