电子阻止截面对平均投影射程计算结果的影响

Influence of the electronic stopping cross section on calculated results of the mean projected ranges

以氦离子轰击碳靶和镍靶为例，通过五种半经验理论计算与实验结果的比较，指出基于ＢＫ模型的通用计算公式可以在很宽能区范围（几ｋｅＶ－几ＭｅＶ）内得到与实验值非常接近的电子阻止截面．还用Ｂｉｅｒｓａｃｋ给出的一阶线性常微分方程表示的平均投影射程算法，研究了不同电子阻止截面对平均投影射程计算结果的影响．结果表明，经选用正确的电子阻止截面公式后，这一简单计算方法可以得到满意的结果．

The electronic stopping cross sections for 4He ions incident on C and Ni targets are calculated with five different formulas and the results are compared with experimental data.A universal formula based on the BK model is considered suitable for the intermediate energy region.Effects of the electronic stopping cross section on the mean projected ranges are investigated by using a linear differential equation derived by Biersack.It is concluded that by choosing an appropriate electronic stopping formula the calculations can be in good agreement with experimental data.