Electron Microscope Observations of Fission Fragment Tracks in Thin Films of UO2

Publisher Website
Google Scholar
Abstract
Electron microscope studies of the tracks produced by fission fragments in thin films of UO2 have established a 100% detection efficiency for fission events in films 100 A or less in thickness. A background texture decreases the efficiency in thicker films. The tracks register in the films primarily as a result of a redistribution of surface material arising from the disturbance produced by the continuous loss of energy of the fragment by electron excitation and ionization. The minimum rate of energy loss which registers as a track in the film is on the order of 1000 ev/A. Track length distributions, however, suggest that as yet unrecognized free surface effects may also contribute to the track registration.