Hyperfine Interactions

, Volume 89, Issue 1, pp 209–218 | Cite as

Near threshold effects in positron-atom (molecule) scattering

  • G. Laricchia
  • J. Moxom
  • M. Charlton
  • á. Kövér
  • W. E. Meyerhof
Invited Papers Session 6. Coupled-Channel Effects


The energy dependence of the total cross-sections for ionization by positron impact has been measured for He, Ne, Ar, CO2 and O2. The interplay between this and other scattering channels has been investigated. The data for He, Ne and Ar has been interpreted using a combination ofR-matrix and threshold theories in the neighbourhood of the Ps formation threshold. In CO2, an enhancement of the Ps formation probability is found when the remnant ion is left in an excited state. In O2, structure has been observed which indicates channel-coupling with excitation to the Schumann-Runge continuum.


Thin Film Excited State Energy Dependence Threshold Effect Formation Probability 
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Copyright information

© J.C. Baltzer AG, Science Publishers 1994

Authors and Affiliations

  • G. Laricchia
    • 1
  • J. Moxom
    • 1
  • M. Charlton
    • 1
  • á. Kövér
    • 1
  • W. E. Meyerhof
    • 2
  1. 1.Department of Physics and AstronomyUniversity College LondonLondonUK
  2. 2.Department of PhysicsStanford UniversityUSA

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