MEDIUM RESOLUTION STUDIES OF EXTREME ULTRAVIOLET EMISSION FROM N-2 BY ELECTRON-IMPACT - THE EFFECT OF PREDISSOCIATION ON THE EMISSION CROSS-SECTION OF THE B1-PI-U STATE

The authors have measured the electron impact induced fluorescence spectrum of N2 in the wavelength range 102 to 134 nm at a spectral resolution of 0.05 nm. The experiment was performed in a crossed beam configuration under optically thin conditions. Their spectral measurements provide the emission cross sections of the transitions of the b1 Pi u-X 1 Sigma +g Birge-Hopfield I-band system. The structure and vibrational population distribution of this system are strongly affected by a configuration interaction of the valence b1 Pi u and Rydberg c1 Pi u and o1 Pi u states. Analysis of electron energy loss data shows that there perturbations give rise to excitation cross sections whose upsilon ' dependence is strikingly different than the variation of the Franck-Condon factors of the unperturbed diabatic states.