Prompt and Time-Delayed Electron Decay-in-Flight Spectra of Gas-Excited Carbon Ions

Little is known experimentally and theoretically about cascade induced repopulation of multiply excited states with high orbital, spin, and angular momentum quantum numbers. Such states are often created with surprisingly large cross sections by the beam-foil or beam-gas interaction. Recent progress in beam-foil and beam-gas1,2 electron spectroscopy offers the possibility to study excitation and deexcitation mechanisms for highly excited ionic projectile states via the Auger decay. This time-of-flight technique allows to analyze the decay of long-lived metastable autoionizing states which are frequently populated by a sequence of cascades that incorporates optical and Auger transitions.