DEEXCITATION OF HOLLOW ATOMS - AUTOIONIZATION OF MULTIPLY EXCITED N, O AND NE ATOMS AT A PT(110) SURFACE

The K-Auger electron emission during the interaction of 60 keV N6+, 70 keV O7+ and 90 keV Ne9+ with a Pt(110) surface occurs below the target surface for glancing angles in the range 10-90-degrees, Therefore the projectile K-Auger electron spectra are distorted by solid state effects. These effects can be removed from the measured spectra by using a procedure originally developped for photoelectron spectroscopy. The resulting primary excitation spectra are compared with results of atomic structure calculations. The analysis reveals that at the instant of K-Auger electron emission on the average five electrons are present in the L-shells of the hydrogen-like N, O and Ne projectiles. Furthermore the ratio of the KLL- and KLM-Auger electron emission yields is determined. It is 3.4, 3.7 and 4.6 in case of the N6+, O7+ and Ne9+ projectile, respectively.