Abstract
In this paper, Solid State Nuclear Detector (SSNTD) CR-39 was broken into many fragments with areas of (1x1) cm2. The samples were irradiated using 241Am source. The measurements were taken at normal incident angle of the alpha particles for energies (3.17, 3.59 and 4.13) MeV respectively. The samples were etched using sodium hydroxide solution (NaOH 6N, 70±1 oC) for time interval of 0.25 h. The optical microscope provided with digital camera was used to preview the track profile formed in CR-39. This allowed measurement of the track length and in turn the track length as a function of the etching time . The track growth rate, track etch rate and track rate ratio were also investigated as a function of many parameters such as etching time, track depth and residual range. The study showed a good consistency among the investigated parameters . The curves of the track etch rate and track etch ratio manifested a consistency with Brack curve who interested in studying the linear energy loss in materials where the maximum energy loss occurs at the end of the alpha particle range.