Classical Self-Ionization of Fast Atomic Ions in Magnetic Fields

In the presence of a magnetic field a permanent exchange of energy between the center of mass and electronic degrees of freedom of the atomic ion is shown to take place. For regular center of mass and internal motion we observe a self-stabilization of the highly excited ion on a Larmor orbit. For large values of the initial center of mass velocity the energy transfer from the center of mass to the electronic degrees of freedom is strong enough to allow the atom to ionize. This dynamical self-ionization effect is studied in some detail. Although the study is based on classical mechanics, it is argued that the effect should be observable in laboratory experiments.