The role of secondary electrons in some experiments determining fluorescence emission from nitrogen C3Î u levels

The processes involved in fluorescence emission from C3Πu levels of N2 molecule by electron impact are studied. Secondary electrons are shown to play an important role in typical experiments for the measurement of emission cross sections and fluorescence yields, dominating at high impact energies. A simple model is proposed which accounts for fluorescence measurements in a wide range of experimental conditions, and in particular for some recent results up to 1 GeV energies.