Empirical Formulas for Ionization Cross Section of Atomic Ions for Electron Collisions. Critical Review with Compilation of Experimental Data

摘要

Based on the comparison with experimental data a critical review is made on empirical cross section formulas for electron-impact ionization of atomic ions. Most extensively studied are the formulas proposed by Lotz and by Golden and Sampson. Several conclusions are drawn about the validity of those formulas. A type of scaling factor is proposed to improve the formula of Golden and Sampson. A compilation of experimental data on electron-impact ionization of atomic ions with Z (atomic number) or = 19 is presented. All the experimental data available are shown in a graphical form with the results of the empirical formulas of Lotz and of Golden and Sampson.