Charged Particle Tracks in Glass

Abstract

Heavily ionizing particles passing through crystalline solids may produce trails of damage which can be seen either directly by electron microscopy or indirectly, by means of preferential chemical dissolution of the damaged material. Where both methods have been used, it has been shown that the method of chemical attack is the more sensitive. Here it is reported that this method of revealing irradiation effects is able also to display the paths of heavy particles in a great many noncrystalline materials, in this instance glass. It is shown that fission fragments from Cf²⁵² leave damage trails in glass which may be etched to give conical pits. In some glasses the cone angles are small, so that the direction taken by the moving particles may be followed. Fission tracks can also be revealed in certain glasses by preferential precipitation of a metal such as silver along the damaged regions. This method has the advantage that a track does not have to intersect a free surface to be revealed.