Abstract
For electron impact ionization of hydrogen the S matrix is determined by calculating Feynman’s path integral semiclassically. The total ionization probability is in excellent agreement with the experiment. At a critical excess energy of 3.3 eV the differential cross section for the energy sharing between the continuum electrons undergoes a qualitative change which limits the range of the threshold behavior. The Wannier threshold law is confirmed, but only in the limt of vanishing excess energy.
- Received 10 September 1993
DOI:https://doi.org/10.1103/PhysRevLett.72.1998
©1994 American Physical Society
