High accuracy electron-impact photoemission cross section measurements for the EUV radiometric standard

This project was concerned with high-accuracy measurements of electron-impact photoemission cross sections for transitions of atoms and molecules in the EUV spectral region (30 nm to 200 nm). The spectrometer-detector system that was employed in the measurements was calibrated using well-parameterized synchrotron radiation. The 58.4 resonance line of He was chosen to establish the overall accuracy of the apparatus and data collection procedures. The measurement of this line can be compared to accurate theoretical calculations and to one other experimental cross section measurement in which a different excitation channel was observed