Alpha particle radiography with the CR-39 nuclear track detector

Abstract

This work studies the alpha particle radiography technique, in conjunction with the CR-39 plastic track detector. The irradiations were made in the CV-28 cyclotron at IEN/CNEN/RJ, using a 7 MeV/nucleon alpha particle beam. All etches were performed by using a 6.25 N NaOH solution, at 70°C. The best etch time to obtain radiographs was determined. A calibration curve (Gray Levels x Energy Loss)was obtained, so as to permit a quantitative interpretation of the images. Its behavior was checked against several experiments with other energy degrading materials, namely, aluminum, mylar and CR-39 itself. The error propagation on energy resolution was also investigated. Several radiographs of in vitro biological specimens were obtained. The results showed the potential capability of this technique for studies in paleontology.