Absolute doubly differential cross sections for the neonK-shell ionization by electron impact

We have measured doubly differential K-shell ionization cross sections in neon by electron impact. Incident energies ranged from 2 to 7 keV and detection angles varied between 20^∘{} and 130^∘{}. The coincidence technique with Auger electrons has been employed to identify K-shell ionization events; the data were brought to an absolute scale by use of previously measured total K-shell ionization cross sections. The results are compared with calculations using the first-order Born and Born-Ochkur approximations. The agreement between theory and experiment is satisfactory if either the energy or the detection angle of the secondary electron is small. The experimental cross sections have been transformed into generalized oscillator strengths, which turned out to be independent of the incident energy, even in those kinematical regions where the first-order Born approximation clearly failed.