Abstract
The classical trajectory method is applied to the investigation of low-energy e+He to He2++3e collisions. In contrast to the hydrogenic case numerical calculations appear unable to derive the ionisation threshold law by varying one or two initial parameters. Final electron energies appear as linear functions of the initial time parameter and it is conjectured that the energy distribution should be uniform within the total energy interval: 0.544<or=E<or=6.75 eV. Calculated angular correlations between the three escaping electrons conform to the full central symmetry at very small energies, but go over to axially symmetric configurations at the energy rises. The final angular momenta acquire large values, with dramatic enhancement at the edges of an ionisation interval, where momentum exchange becomes particularly strong. Finally, the applicability of the classical model to non-hydrogenoics is discussed, as well as some stochastic effects encountered.