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An Explanation of the Structure Observed in Out-Of-Plane Symmetric Measurements on Helium

  • J. Rasch
  • Colm T. Whelan
  • R. J. Allan
  • H. R. J. Walters
Part of the Physics of Atoms and Molecules book series (PAMO)

Abstract

The study of (e,2e) processes on Helium at impact energies of 100eV and below has yielded a wealth of experimental data and has contributed greatly to the understanding of the Coulomb few body problem. The great advantage of coincidence measurements is that one can manipulate the geometry of the experiment to study delicate processes which yield striking structures in a particular arrangement, but are largely masked by stronger effects in virtually all other setups. Quite recently Murray1 identified a very strong structure in the ionization of Helium at an impact energy of 64.6eV in a very specific out of plane geometry. In this paper we will show that this structure is well represented in a Distorted Wave Born Approximation (DWBA) calculation and we will interpret it as an interference, that is to say a pure quantum, effect. We predict that similar structures will be present in the Triple Differential Cross Section (TDCS) for some targets but not for others.

Keywords

Impact Energy Distorted Wave Interference Structure Final Channel Distort Wave Born Approximation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1997

Authors and Affiliations

  • J. Rasch
    • 1
  • Colm T. Whelan
    • 1
  • R. J. Allan
    • 2
  • H. R. J. Walters
    • 3
  1. 1.Department of Applied Mathematics and Theoretical PhysicsUniversity of CambridgeCambridgeEngland
  2. 2.Daresbury LaboratoryWarringtonEngland
  3. 3.Department of Applied Mathematics and Theoretical PhysicsThe Queen’s University of BelfastBelfastEngland

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