Track Revelation and Observation

Abstract

Due to their limited width of a few nm, a direct observation of latent fission tracks is only possible with transmission electron microscopy (TEM) and the early observations of tracks in mica were made with this method (Silk and Barnes, 1959; Price and Walker, 1962a,b) using the electron beam in a diffraction contrast mode. In order to render the damage trails visible under a normal optical microscope, several techniques of track enlargement, also called visualization or revelation techniques, have been developed. An overview of these techniques and their application in the various fields of nuclear track detection has been given by Fleischer et al. (1975) and Monnin (1980). A first group of revelation techniques are the so-called decoration techniques. Examples are segregation and precipitation of metals along the damage trails (Fleischer and Price, 1963b) and polymerization followed by subsequent dyeing (Monnin and Blanford, 1973; Somogyi et al., 1979). Decoration techniques are essentially used on plastics and have not found application in fission-track dating.