ELECTRON-IMPACT EXCITATION OF HELIUM TO 23S,33S,43S STATES AT INTERMEDIATE ENERGIES

Differential cross sections for the electron impact excitation from the ground state to the 23S, 33S and 43S states of helium at impact energies 200 and 300 eV, are calculated in the two potential model and using the modified plane wave approximation. The results are compared with the available experimental data and other theoretical calculations. It is shown that the present procedure provides significant improvement over the plane wave approximation. © 1979, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.