High-resolution Be Auger spectroscopy using fast Be ion beams excited in single gas collisions

Be Auger spectra are studied by 25-500 keV Be+ ion impact on H2, He, CH4 and Ne. Several single and doubly core-excited states not previously seen are identified by comparison with calculated transition energies. In particular metastable autoionising Be II (1s2s2p)4P0 states are strongly populated.