Angle-resolved resonant Auger electron spectroscopy of CO after vibrationally resolved C 1s -> nl lambda excitations

Angle-resolved resonant electron spectra following vibrationally resolved C Is --> nl lambda (nu = 0, 1) excitations in CO have been measured. The obs erved groups of resonant Anger lines exhibit great similarity in shape to t he C-KVV group of non-resonant Auger lines and the observed angular distrib ution behaviour reflects the symmetry-dependent anisotropies of the excitat ion process. The molecular progressions in the C Is --> pi* resonant Auger spectrum could be clearly identified due to their different angular distrib ution behaviour. Furthermore, it could be shown that the screening energies for spectator electrons over binding energy have a linear dependence betwe en 3p pi, 4p pi and threshold as was expected for the higher p-symmetry Ryd berg orbitals.