Radiation Application Research School, Nuclear Science and Technology Research Institute (NSTRI), Tehran, Iran.
Physics Department, K. N. Toosi University of Technology, Tehran, Iran.
Sci Rep. 2023 Mar 2;13(1):3573. doi: 10.1038/s41598-023-30491-5.
As an important component in medical applications, dosimetry, and radiotherapy studies, the effective atomic number of body tissue, tissue equivalent substances, and dosimetry compounds are investigated. In this research, considering the Coulomb interaction of charged particles, using the collision stopping power and the NIST library data, the effective atomic number of various materials at different energies is calculated for common radiotherapy particles such as electron, proton, alpha, and carbon ions. Taking into account the direct calculation method based on the collision stopping power, the effective atomic number for electron, proton, alpha, and carbon particles is determined for a group of dosimetry and tissue equivalent materials. Results of the calculations based on the collision stopping power showed that in low kinetic energy, the values of the effective atomic number are equal to the total number of electrons in each molecule of the compound, which is quite justified by the physics of Bethe's formulas.
作为医学应用、剂量学和放射治疗研究的重要组成部分，研究了体组织、组织等效物质和剂量学化合物的有效原子数。在这项研究中，考虑到带电粒子的库仑相互作用，利用碰撞阻止本领和 NIST 库数据，计算了电子、质子、α 和碳离子等常见放射治疗粒子在不同能量下各种材料的有效原子数。考虑到基于碰撞阻止本领的直接计算方法，确定了一组剂量学和组织等效材料中电子、质子、α 和碳粒子的有效原子数。基于碰撞阻止本领的计算结果表明，在低动能时，有效原子数等于化合物每个分子中的总电子数，这与 Bethe 公式的物理原理非常吻合。
