POSITRONIUM SCATTERING BY HELIUM
 Jennifer Blackwood$^+$, C.P.Campbell$^+$, Mary T.McAlinden$^*$
and H.R.J.Walters$^+$
 ${}^+$Department of Applied Mathematics, Queen's University,
Belfast BT7 1NN, UK.
 ${}^*$ School of Computing, Staffordshire University,
Beaconside, Stafford ST18 0DG, UK.
We report results of extensive calculations of positronium -
helium scattering within the coupled - pseudostate formalism.
These calculations give a complete picture of all the main
processes over the energy range 0 to 40eV.