Generalised oscillator strength for the core level excitation of nitrogen in N2, NO and N2O by electron impact

The excitation of nitrogen 1s electrons to the first unfilled pi 2p orbital has been studied in N2, NO and N2O by electron energy loss spectroscopy at incident energies of 1400 and 3400 eV. The absolute generalised oscillator strength and its dependence on the momentum transfer have been derived from the angular distribution of the differential cross section over a large range of the momentum transfer. The extrapolated optical oscillator strength has also been obtained. The results are compared with previous experimental results and calculations.