Measurement of the Impact Ionisation and Positronium Formation Cross Sections for Positron Scattering on Molecular Hydrogen

  • Dieter Fromme
  • Georg Kruse
  • Wilhelm Raith
  • Günther Sinapius
Part of the NATO ASI Series book series (NSSB, volume 169)


We measured the impact ionisation and positronium-formation cross sections for positron scattering on molecular hydrogen with the same experimental set-up used for our measurements on helium.1 As in the case of helium the positron impact-ionisation cross section (not including positronium formation) exceeds the corresponding electron cross section2 in the energy range around the respective maxima (Fig. 1). It is lower than the electron cross section right above ionisation threshold. This is in accordance with the Wannier threshold law, as described earlier.3


Energy Range Federal Republic Molecular Hydrogen Impact Ionisation Atomic Physic 
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Copyright information

© Plenum Press, New York 1987

Authors and Affiliations

  • Dieter Fromme
    • 1
  • Georg Kruse
    • 1
  • Wilhelm Raith
    • 1
  • Günther Sinapius
    • 1
  1. 1.Fakultät für PhysikUniversität BielefeldBielefeldFederal Republic of Germany

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