Optical appearance of alpha-particle tracks in CR-39 SSNTDs

The optical appearance of etched alpha-particle tracks in CR-39 SSNTDs under the transmission mode of the optical microscope were studied. The mean grey levels revealed using a digital camera installed on the microscope, together with the major and minor axes were systematically determined for tracks from alpha particles with different incident energies and angles. The grey level properties for the same track could vary to large extents, which could be corrected using optimum operation conditions of the camera. Differentiation among recorded tracks was then automated using a computer program, for which the grey levels, major and minor axes values were used as inputs and from which the angle and energy of the incident alpha particles were given as the outputs. The accuracy of the determined alpha-particle energy is 0.5 MeV.