The influence of the σ resonance on the Auger decay of core-ionized molecular nitrogen

Auger spectra from the decay of core-ionized N2 have been studied as a function of the exciting photon energy. Discrete features appear in the Auger spectrum when the photon energy is tuned to the shape-resonance region at 420 eV. The Auger spectra for two final dicationic states are studied; simulations of the contributions from the decay of the gerade and ungerade core-hole states are made based on a Franck–Condon picture including life time vibrational interference. We are able to reproduce the vibrational fine structure in the Auger spectrum using a model where the coherent sum of the decay channels from the vibrationally-excited states are treated separately for the gerade and ungerade states.