Chaotic versus random ionization - art. no. 047202

We use Kepler maps to study the classical ionization of the hydrogen atom d riven by electric fields; we compare the ionization rate (IR) due to chaoti c motion (constant field amplitude) with the IR due to randomness (random f ield amplitude). We find that for weak fields the ionization due to random amplitude is more effective, while for strong fields the ionization due to chaos is more effective; so, there is a cross of such ionization curves. A physical explanation of this phenomenon, based on the trajectory behavior, is given.