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 distorted‐wave Born approximation (DWBA) has been one of the most successful
theoretical approaches for treating electron collisions with complicated atoms, and recently …

We determine, both experimentally and theoretically, the fully resolved fivefold differential
cross section (5DCS) of double ionization of helium by 5.6 keV electron impact. Symmetric …

The dynamics of He double ionization by 2 keV electron impact is studied experimentally for
a momentum transfer of 0.6 au at excess energies of 10 and 40 eV. Complete sets of fivefold …

Currently there are no reliable theoretical approaches for calculating fully differential cross
sections (FDCSs) for low-energy electron-impact ionization of large molecules. We have …

The four-particle process of proton-helium transfer ionization has been studied using cold
target recoil ion momentum spectroscopy to measure the momenta of all three particles in …

Over the past two decades impressive progress has been made in the theoretical and the
experimental study of the multiple excitation and of the complete fragmentation of four-body …

The study of structure and collision processes of three-and four-body problems has seen an
extraordinary progress in the last decades. This progress has been in part associated to the …

Recently, absolute measurements have been reported for double ionization of helium by 5.6
keV electron-impact. At this high energy, one would think that the first Born approximation for …

We develop two variational wave functions of helium which give accurate energy values and
satisfy Kato's cusp conditions adapted to the variational procedure. These wave functions …