Development of a new code for stopping power and CSDA range calculation of incident charged particles, part A: Electron and positron

Abstract

The stopping power of targets against incident charged particles and their range through matter are commonly considered as two important parameters in radiation and health physics studies. The exact calculation of these parameters is very crucial in many applications of radiation. The main objective of this study is the development of a new code for stopping power and range calculation of incident electron and positron projectiles. In this case, the interactions with matter are mainly due to the collision process and the Bremsstrahlung radiation emission. For collision stopping power, the Moller and Bhabha relations were considered for electron and positron, respectively. Some sophisticated correlations based on the Fano model have been selected for density correction term. For the radiative stopping power, a multifunction analytical model was developed based on an extensive literature review. All the equations were consolidated and programmed via the development of a new computational code using the C# programming language. Some simple and compound generic materials were considered for the verification process. Graphite, Silicon and Copper were selected as simple materials; whilst compound materials include air, water and the A-150- Tissue-Equivalent Plastic (A150TEP). The results of the stopping power and the range of incident particles were compared with well-known ICRU reports as well as Monte Carlo simulation. The results are consistent and in agreement with reference data. The maximum relative error of the collision stopping power was about 5% in comparison with ICRU reports for both electron and positron. However, for the positron projectile at low energies, some minor discrepancies were observed between the calculated collision stopping power and the MCNPX data. For the radiative stopping power, some deviations were observed in the low energy region and the model borders. The maximum relative error in the total stopping power was about 5–6% in comparison with ICRU reports and 15–20% in comparison with the MCNPX.