ELECTRON IMPACT EXCITATION - IONIZATION OF HELIUM : (e, 2e)
Pascale Marchalant+, J.Rasch++, Colm T.Whelan++ and
H.R.J.Walters*
+Institut fur Theoretische Physik, Universitat Frankfurt
D-60054 Frankfurt, Germany.
++Department of Applied Mathematics, University of Cambridge,
Cambridge CB3 9EW, UK.
*Department of Applied Mathematics, Queen's University,
Belfast BT7 1NN, UK.

Accurate first Born calculations of (e, 2e) excitation - ionization
of He to He+(n=2) will be presented. These calculations employ
large coupled - pseudostate expansions for the final state wave
function representing the ejected electron moving in the field of
He+(n=2).