Research Papers in Physics and Astronomy


Date of this Version



Published in Physical Review A Volume 38, Number 7, October 1, 1988. Copyright © American Physical Society; used by permission.


Discrepancies between previous experimental values of differential cross sections for electron-impact ionization of water vapor and recent model calculations have been largely resolved. A new measurement with improved suppression of spurious electrons has removed most of the discrepancy in the midrange of detected electron energies. A second discrepancy at secondary energies just below the primary energy has been explained by a more accurate accounting for electrons scattered at angles between zero and the minimum angle of the experimental apparatus. The improved data show more clearly the oxygen K-shell edge in the spectra at small angles and the Bethe ridge at angles up to 90". The forward peak seen in the earlier data is no longer present.

Included in

Physics Commons