The substantial progress that has occurred during the 1990s in the field of electron-atom-
collision theory is discussed. We show how a solution of a small-model three-body problem …

The past decade has seen extraordinary theoretical progress in the field of fully
kinematically resolved atomic electron-impact ionisation, and its closely related field of …

Recoil-ion and electron momentum spectroscopy is a rapidly develo** technique that
allows one to measure the vector momenta of several ions and electrons resulting from …

A general formalism is presented for the calculation of simultaneous electron-impact
ionization-excitation in a model that accounts for interactions up to second order of the …

We develop a theoretical model to describe simultaneous ionization excitation and double
ionization of a two-electron atomic shell (ie, He 1 s 2) by a fast charged-particle impact. The …

We present experimental and theoretical results for the electron-impact-induced ionization of
ground-state helium atoms. Using a high-sensitivity toroidal electron spectrometer, we …

Simultaneous ionization and excitation of helium atoms by 500 eV electron impact is
observed by a triple coincidence of an ionized slow electron, the recoiling He+ ion, and the …

We present high-precision (e, 2 e) measurements and calculations for the e-He four-body
Coulomb breakup problem. Cross-section ratios for ionization and excitation of the first three …

R-matrix theory was introduced by Wigner, 1946a, Wigner, 1946b and Wigner and Eisenbud
(1947) in fundamental papers describing nuclear resonance reactions. This and other early …

We report detailed calculations of the first Born triple-differential cross section for (e, 2e)
excitation-ionization of ground state He to He+(n= 2). These are in accord with the very …