Medium resolution studies of extreme ultraviolet emission from N2by electron impact: the effect of predissociation on the emission cross section of the b1Πustate

Abstract

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-X¹ 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.