Simulation of atomic ionization following the α decay of the nucleus

When the nucleus of an atom decays by emitting an α particle, the surrounding electrons are perturbed and the atom may be ionized. We consider two types of schematic one-dimensional models, I and II, that simulate this ionization process. In model I the α particle is treated as a classical point charge that is emitted by the nucleus at a certain time and travels out at constant speed. This model simulates Migdal's method, on which virtually all calculations performed so far for the ionization process are based. Migdal's method yields an ionization probability that is in reasonable agreement with experiment. In model II, the α particle is treated as a quantum mechanical wave that slowly leaks out from the nucleus. The ionization probability that follows from model II, however, is far smaller than that of model I. Implications of this difference are discussed.