Electron impact excitation and ionization of laser-excited Na atoms

Abstract

Electron spectra for 1.5 keV electron impact on Na are measured for one-step laser excitation to Na(3p 3 2 ) and for two-step laser excitation to Na(4d 5 2 ) or Na(5s). Auger states Na + (2s2p 6nl) with nl=3p, 4p, 5p; 5s, 6s, 7s; 4d, 5d, 6d are observed, most of them cannot be reached by ionization of the ground state atom Na(3s). State energies, shake probabilities, total and partial decay widths are given and discussed.