Spectroscopic analysis of alpha particles from radioactive nuclides with CR-39 plastic nuclear track detectors.

A spectroscopy method of alpha particles with the track geometry parameters in CR-39 plastic nuclear track detectors is proposed. The relationship between the track registration sensitivity and incident angle of each etch pit is analyzed. The components of alpha particles emitted from radon, thoron and 241Am can be roughly separated when the etching level is not exceeded beyond the range in CR-39. This work aims at improving the dose assessment accuracy from exposure to indoor radon and thoron.