Evidence against atomiclike resonant Auger decay inN2doubly excited core states by high-resolution experiments

Abstract

Resonant Auger spectra following the decay of doubly excited core states in ${\mathrm{N}}_{2}$ in the range 409--411 eV have previously been assigned to ``atomic'' lines indicating ultrafast dissociation. Using high-resolution synchrotron radiation electron spectroscopy from the MAX II facility in Sweden we have remeasured the resonant Auger spectrum of ${\mathrm{N}}_{2}$ in the vicinity of the N $1s$ threshold. Contrary to earlier studies, we find vibrational progressions that can be associated with the final $C{}^{2}{\ensuremath{\Sigma}}_{u}^{+}$ and $2{}^{2}{\ensuremath{\Pi}}_{g}$ states in ${\mathrm{N}}_{2}^{+}.$ We conclude that the decay leads entirely to molecular final states.