Double photoionization of N2 into the N22+ D 1Σu+-state

Double photoionization of N2 into the N22+D1Σ u+-state as a function of the exciting-photon energy has been investigated experimentally and theoretically. Photon-induced fluorescence spectroscopy using monochromatized synchrotron radiation in the exciting-photon energy range between 50 and 66.5 eV and recording of the intensity of the dispersed VUV fluorescence between 145 and 167 nm has been carried out. Relative cross sections as a function of the exciting-photon energy have been determined. The experimental results are compared with ab initio calculations.