SEMIEMPIRICAL FORMULAS FOR DIPOLE EXCITATION CROSS-SECTIONS AND RATE COEFFICIENTS IN ATOMS AND IONS

Analytical semiempirical formulae for the cross sections and corresponding rate coefficients are suggested for allowed transitions (DELTA-l = +/- 1) in atoms and ions induced by electrons with energies E >> DELTA-E, where DELTA-E is the transition energy. These formulae were obtained using the model dipole interaction potential and numerical calculations of the excitation cross sections. The results are compared with other semiempirical formulae and computer calculations.