THEORETICAL STUDIES OF LOW ENERGY POSITRON SCATTERING BY AN
EQUIVALENT ONE-ELECTRON MODEL OF HELIUM


J.T. Dunn, P. Van Reeth and  J.W. Humberston


Department of Physics and Astronomy, 

University College London,
Gower Street, London WC1E 6BT, UK

Theoretical investigations using a very elaborate scattering
wavefunction and an accurate one-electron model of helium are being made
to study the elastic scattering, positronium formation and annihilation
cross sections.