Akar Ayşegül, Gümüş Hasan, Okumuşoğlu Nazmi T
Department of Physics, Faculty of Arts and Sciences, Ondokuz Mayis University, Samsun 55139, Turkey.
Appl Radiat Isot. 2006 May;64(5):543-50. doi: 10.1016/j.apradiso.2005.11.014. Epub 2006 Jan 4.
In this study, for low atomic number targets and biological compounds, an inelastic mean free path (IMFP) formula and energy straggling parameter formula are presented, being valid for low and high electron energies. In addition, calculation of the continuous slowing down approximation-range (CSDA-range) from the stopping power is also made. The IMFP and the energy straggling parameter formulae are evaluated using the generalized oscillator strength (GOS) model and the exchange correction to the inelastic differential cross section (IDCS) given by Inokuti, M., [1978. Inelastic collisions of fast charged particles with atoms and molecules--the Bethe theory revisited. Rev. Mod. Phys. 50, 23-35]. The IMFP and CSDA-range for the biological compounds C5H5N5 (adenine), C5H5N5O (guanine), C4H5N3O (cytosine), C5H6N2O2 (thymine), C20H27N7O13P2 (cytosine-guanine) and C19H26N8O13P2 (thymine-adenine) have been introduced for incident electrons in the energy range 20 eV-1 MeV. The calculated results are compared with semi-empirical results and other theoretical results, good agreement being found with experimental data and Monte Carlo (PENELOPE code) predictions. All the IMFP versus energy curves exhibit minima around 80 eV.
在本研究中，针对低原子序数靶材和生物化合物，给出了一个非弹性平均自由程（IMFP）公式和能量离散参数公式，它们在低电子能量和高电子能量下均有效。此外，还根据阻止本领计算了连续慢化近似射程（CSDA射程）。使用广义振子强度（GOS）模型和Inokuti, M. [1978年。快速带电粒子与原子和分子的非弹性碰撞——重温贝特理论。《现代物理评论》50, 23 - 35]给出的非弹性微分截面（IDCS）的交换修正来评估IMFP和能量离散参数公式。引入了生物化合物C5H5N5（腺嘌呤）、C5H5N5O（鸟嘌呤）、C4H5N3O（胞嘧啶）、C5H6N2O2（胸腺嘧啶）、C20H27N7O13P2（胞嘧啶 - 鸟嘌呤）和C19H26N8O13P2（胸腺嘧啶 - 腺嘌呤）在20 eV - 1 MeV能量范围内入射电子的IMFP和CSDA射程。将计算结果与半经验结果和其他理论结果进行了比较，发现与实验数据和蒙特卡罗（PENELOPE代码）预测结果吻合良好。所有IMFP与能量的曲线在80 eV左右都呈现出最小值。
