Argon L23-MM Auger satellite spectrum emitted after K ionization

Auger satellites arising from transitions in the presence of 'spectatorY vacancies have minor intensity in electron impact excited spectra. They are, however, very efficiently produced if preceded by another Auger transition. We have measured the L 23 -MM Auger spectrum of argon emitted after photoexcitation with broad-band synchrotron radiation of energies largely lying above the K-shell ionization potential. The spectrum exhibits a high degree of line overlap and is shown to be a superposition of at least six L 23 -MM spectra belonging to various configurations of spectator vacancies and having comparable overall intensities. We made relativistic calculations in configuration average which reproduce the general appearance of the complex spectrum quite well. A number of lines in the L 23 (L 23 )-M 23 M 23 (L 23 ) and L 23 (M 23 2 )-M 23 M 23 (M 23 2 ) spectra have been analysed and five L 23 -1 M 23 -2 states have been energetically located.