AUGER-ELECTRON EMISSION FROM SLOW, HIGHLY CHARGED IONS INTERACTING WITH SOLID CU TARGETS

Secondary-electron energy spectra were measured for Ar(q+) (q = 9 and 16) and the H-like ions N6+, O7+, and Ne9+, incident on solid Cu surfaces at an angle of 10-degrees. The impact energy was varied from 10q to 20q keV. Auger electrons were detected at various observation angles from 20-degree to 180-degrees with respect to the incident beam. From the Doppler shift of the projectile Auger electrons, the L Auger electrons of argon and neon are found to be emitted from ions whose flight direction is parallel to the incident beam and the K Auger electrons of nitrogen, oxygen, and neon are observed to be emitted from deflected ions. Evidence is provided for incident Ne9+ and Ar16+ that the L shells are incompletely filled when the projectiles reach the surface. The data analysis is supported by model calculations.